Screening Tests for Adults (Ages 30-49)

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Screening tests are an important part of your preventive health care. For people between the ages of 30 and 49, these tests are used for early detection of some of the more common and potentially deadly diseases—such as cancersdiabetes, and heart disease—that begin to affect people in their middle years. These tests can help catch certain illnesses and conditions in their earliest and most curable stages, even before you notice symptoms.

With information from screening tests, your healthcare provider can work with you to develop preventive measures that will improve your health and can even extend your healthy years. For example, a routine cholesterol test could reveal your risk for developing heart disease, allowing you to take preventive steps—like lifestyle changes—before you develop a serious condition.

The sections below provide information on the screening tests suggested for adults 30 to 49 years old. They summarize the recommendations from various authorities, and there is consensus in many areas, but not all. Therefore, when discussing screening with your healthcare provider and making decisions about testing, it is important to consider your individual health situation and risk tolerance.

For more information on preventive medicine and steps you can take to keep you and your family healthy, read Wellness and Prevention in an Era of Patient Responsibility.

Not everyone in this age group may need screening for every condition listed here. Read the sections below to learn more about each condition and to determine if screening may be appropriate for you or your family member. You should discuss screening options with your health care practitioner.

Screening Recommendations

High Cholesterol

Beginning in childhood, the waxy substance called cholesterol and other fatty substances known as lipids start to build up in the arteries, hardening into plaques that narrow the passageway. During adulthood, plaque buildup and resulting health problems occur not only in arteries supplying blood to the heart muscle but in arteries throughout the body (a problem known as atherosclerosis). For both men and women in the United States, the number one cause of death is heart disease, and the amount of cholesterol in the blood greatly affects a person’s chances of suffering from it.

Monitoring and maintaining healthy levels of cholesterol are important in staying healthy. Screening for high cholesterol, typically with a lipid profile, is important because there are usually no symptoms. A lipid profile usually includes total cholesterolHDL-cholesterolLDL-cholesterol, and triglycerides and sometimes non-HDL cholesterol. Typically, fasting for 9-12 hours (water only) before having blood drawn is required, but some labs offer non-fasting lipid testing.


Since recommendations are not always consistent between healthcare organizations, it’s important to work with your healthcare provider to develop a cholesterol-screening plan that is right for you.

  • The American Heart Association recommends that all adults 20 years of age and older have cholesterol testing (a fasting lipid profile) every 4-6 years. More frequent testing is recommended for those at increased risk.
  • The U.S. Preventive Services Task Force (USPSTF) advises healthcare practitioners and their patients to go beyond screening for high cholesterol and evaluate a person’s overall risk for heart disease to determine who may benefit from treatment with statins.The USPSTF’s 2016 guidelines do not recommend for or against cholesterol screening in people aged 21 to 39. This is based on a lack of evidence that screening before age 40 has an effect on cardiovascular health. The USPSTF recommends that clinicians use their judgment when deciding to screen people in this age group.For people aged 40 to 75 years, rather than screening, the USPSTF recommends assessing the individual’s overall risk of heart disease and if they will benefit from statin treatment.The guidelines also note that statins may not be the answer for everyone with risk factors. Regardless of heart disease risk, everyone can benefit from lifestyle changes that reduce the chance of developing heart disease.

Risk Factors

Examples of risk factors include:

  • Family history of early heart disease (heart disease in a first degree male relative under age 55 or a first degree female relative under age 65)
  • Smoking cigarettes and using tobacco products
  • Diabetes or prediabetes
  • High blood pressure (hypertension) or you take blood pressure medications
  • Obesity or being overweight
  • Unhealthy diet
  • Physical inactivity, not getting enough exercise
  • Pre-existing heart disease or already having had a heart attack

University of Maryland Heart Center: Heart Disease Risk Calculator
National Heart, Lung, and Blood Institute: High Blood Cholesterol

Sources Used in Current Review (last reviewed 7/12/17)

(2008, June). Lipid disorders in adults (cholesterol, dyslipidemia): Screening. U.S. Preventive Services Task Force. Available online at Accessed June 2017.

(2016 February 9). High cholesterol, symptoms and causes. Mayo Clinic. Available online at Accessed June 2017.

(Reviewed 2016 June). Understand your risks to prevent a heart attack. American Heart Association. Available online at Accessed June 2017.

(2016 November 15). Statin Use for the Primary Prevention of Cardiovascular Disease in Adults. US Preventive Services Task Force Recommendation Statement. JAMA 2016; 316(19):1997-2007. doi:10.1001/jama.2016.15450. Available online at Accessed June 2017.

(Reviewed 2017 April). How to get your cholesterol tested. American Heart Association. Available online at Accessed June 2017.

(Reviewed 2017 June). Heart-health screenings. American Heart Association. Available online Screenings_UCM_428687_Article.jsp#.WUsaFxPyvR0. Accessed June 2017.

Family History of Early Atherosclerotic Cardiovascular Disease. National Heart, Lung and Blood Institute. Available online at Accessed June 2017.


Obesity is a serious, growing health problem in the U.S. Over the past 20 years, the rate of obesity has increased steadily throughout the U.S. in all age ranges. Currently, about 42% of adults in the U.S. have obesity and about 9% have severe obesity, according to the Centers for Disease Control and Prevention (CDC).

Obesity is a complex condition with several contributing factors, such as behaviors, environment and community, underlying diseases, and medications. According to the CDC, genes also play a role in developing obesity.

Obesity is a serious health concern because it decreases overall quality of life and increases the risk of many conditions and diseases, such as:

Calculating your body mass index (BMI) can be a useful screening tool for assessing your weight status.

For adults, the following formula and classifications are used:

BMI = (Weight in pounds) / (height in inches squared) x 703

Body Mass Index Definition
Less than 18.5 Underweight
18.5 to 24.9 Normal weight
25.0 to 29.9 Overweight
30 and above Obese

Obesity is often further divided into categories:

Body Mass Index Category
30 to 34 Class 1
35 to 39 Class 2
40 or higher Class 3 (extreme or severe obesity)

While BMI is a useful screening tool, it is not diagnostic of your health status. Your healthcare practitioner will perform various health exams and consider several factors to evaluate your overall health and risk of conditions and diseases.

Screening Recommendations

  • The U.S. Preventive Services Task Force recommends that healthcare practitioners offer or refer patients with a BMI of 30 or higher to intensive programs. These programs offer several strategies to change behaviors, to reduce weight, and increase activity. The American Academy of Family Physicians supports these recommendations.
  • The Canadian Task Force on Preventive Health Care recommends that healthcare practitioners screen for obesity in all adults at primary care visits by measuring BMI.
  • Several other health organizations, such as the American College of Cardiology, the American Heart Association, and the National Institute for Health and Care Excellence, recommend regularly screening adults for obesity by measuring waist circumference and/or BMI.

Regular screening may show that your weight is increasing over time. Your healthcare practitioner may recommend lifestyle changes to reverse this trend. For example, eating a healthy diet and getting regular exercise may help prevent you from becoming overweight or obese.

If you are diagnosed as being overweight or obese, your healthcare practitioner may recommend treatment. Treatment depends on the cause and severity of obesity and may include medications for weight loss. Consultation with a surgeon who specializes in weight loss surgery may be considered by some people.

Sources Used in Current Review (last reviewed July 2020)

(September 18, 2018) U.S. Preventive Services Task Force. Weight Loss to Prevent Obesity-Related Morbidity and Mortality in Adults: Behavioral Interventions. Available online at Accessed July 2020.

Copyright © 2020 American Academy of Family Physicians. Clinical Preventive Service Recommendation: Obesity. Available online at Accessed July 2020.

Centers for Disease Control and Prevention. Adult Overweight and Obesity. Available online at Accessed July 2020.

National Heart, Lung, and Blood Institute. Overweight and Obesity. Available online at Accessed July 2020.

The Canadian Task Force on Preventive Health Care. Obesity in Adults (2015). Available online at Accessed July 2020.


Diabetes is the seventh leading cause of death in the United States. The Centers for Disease Control and Prevention (CDC) estimates that 30.2 million people age 18 and older, or 12.2% of all people in this age group, have diagnosed or undiagnosed diabetes. Of these, 4.6 million are 18-44 and 14.3 million are 45-64 years old. Type 2 diabetes accounts for 90-95% of all diagnosed cases of diabetes among adults. Unhealthy weight and physical inactivity, also significant national health problems, are both contributing factors to the rising incidence of type 2 diabetes.

Another 84.1 million American adults age 18 years or older have prediabetes, meaning that their blood glucose levels are higher than normal but not yet high enough to be diagnosed with diabetes. Detecting prediabetes allows individuals to take steps to stop or slow the development of type 2 diabetes and its complications. These complications include heart attackstrokehypertension, blindness and eye problems, kidney disease, and nervous system maladies. More than 60% of lower limb amputations occur in people with diabetes.

Risk Factors
Being overweight – having a body mass index (BMI) equal to or greater than 25 kg/m2 – is a major risk factor for type 2 diabetes.

Other risk factors related to your own health include:

  • Physical inactivity
  • Having high blood pressure (hypertension), meaning blood pressure 140/90 mmHg or higher or receiving therapy for hypertension
  • History of cardiovascular disease
  • Having a HDL-cholesterol level less than 40 mg/dL (1.00 mmol/L) and/or a triglyceride level greater than 150 mg/dL (1.70 mmol/L)
  • Having a previous hemoglobin A1c test result equal to or greater than 5.7%, impaired glucose tolerance (glucose tolerance test result 140 to 199 mg/dL (7.8 to 11.1 mmol/L)), or impaired fasting glucose (fasting glucose level 100 to 125 mg/dL (5.6 to 6.9 mmol/L))
  • Having conditions associated with insulin resistance, such as severe obesity and acanthosis nigracans

Family-related risk factors are:

  • Having a parent or sibling with diabetes
  • Being of African American, Latino, Native American, Asian American, or Pacific Islander descent

Women’s risk factors include:

Screening tests for men and non-pregnant women

  • Fasting glucose (fasting blood glucose, FBG) – this test measures the level of glucose in the blood after an 8-12 hour fast.
  • Hemoglobin A1c (also called A1c or glycated hemoglobin) – this test evaluates the average amount of glucose in the blood over the last 2 to 3 months and has been recommended as another test to screen for diabetes.
  • 2-hour glucose tolerance test (OGTT) – this test involves drawing a fasting blood sample for glucose measurement, followed by having the person drink a solution containing 75 grams of glucose and then drawing another sample two hours after the person begins to consume the glucose solution.

If any of these results is abnormal, the test is repeated on another day. If the repeat result is also abnormal, a diagnosis of diabetes is made.

The American Diabetes Association (ADA) and the U.S. Preventive Services Task Force (USPSTF) recommend the following:

  • If you are age 45 or older, you should be screened.
  • If you are younger than 45 but overweight or have any of the other risk factors, consider diabetes screening.
  • Even if initial screening results are normal, get repeat testing at least every 3 years, say the ADA and USPSTF. If you are identified as having prediabetes, get tested yearly.

The American Association of Clinical Endocrinologists (AACE) also recommends diabetes screening for asymptomatic people with these risk factors, as well as those on antipsychotic therapy for schizophrenia or who have severe bipolar disease.

As public health experts work to educate Americans on what to do to avoid diabetes and its serious complications, be aware that healthy eating habits and activity choices can lower your risk of developing type 2 diabetes and of suffering complications from the disease.

NIDDK: Preventing Type 2 Diabetes
American Diabetes Association
National Diabetes Education Program
Centers for Disease Control and Prevention: Type 1 or Type 2 Diabetes and Pregnancy

Sources Used in Current Review (last reviewed 9/18/17)

(2017). National diabetes Statistics Report, 2017. Centers for Disease Control and Prevention. Available online at Accessed on 8/06/17.

(2015 October). Abnormal Blood Glucose and Type 2 Diabetes Mellitis: Screening. U.S. Preventive Services Task Force. Available online at Accessed on 8/06/17.

(2017 July 27, Updated). What’s New in Diabetes. Centers for Disease Control and Prevention. Available online at Accessed on 8/06/17.

(2017 July 25, Updated). Who’s at Risk? Centers for Disease Control and Prevention. Available online at Accessed on 8/06/17.

Genzen, J. et. al. (2017 July, Updated). Diabetes Mellitus. ARUP Consult. Available online at Accessed on 8/06/17.

(2016 November). Diabetes Tests & Diagnosis. National Institute of Diabetes and Digestive and Kidney Diseases. Available online at Accessed on 8/06/17.

(2015). Screening and Monitoring of Prediabetes. American Association of Clinical Endocrinologists. Available online at Accessed on 8/06/17.

Diabetes Management Guidelines, American Diabetes Association (ADA) 2016 Guidelines. National Diabetes Education Initiative. Available online at Accessed on 8/06/17.

High Blood Pressure

Almost half of adults in the U.S. have high blood pressure, according to the American Heart Association. Blood pressure is the force that your blood puts on your artery walls. High blood pressure, also called hypertension, happens when that force is consistently too high.

Detecting and treating high blood pressure is important because over time, it can damage your circulatory system and increase your risk of a heart attackstroke, and other health problems later in life. In fact, hypertension contributes to one out of every seven deaths in the U.S. In general, the longer you have high blood pressure, the greater the potential for damage to your heart and other organs including your kidneys, brain, and eyes.

High blood pressure before age 40 is a risk factor for developing heart disease later in life.

Most people with high blood pressure aren’t aware of it because there are often no obvious symptoms. The only way to find out if you have high blood pressure is to get tested.

How is blood pressure measured?

Blood pressure was traditionally measured in healthcare settings using a blood pressure cuff with a pressure gauge (sphygmomanometer). This air-filled cuff wraps around the upper arm and obstructs blood flow. By releasing small amounts of air from the cuff, blood slowly flows back into the arm. The pressure measured inside the cuff is the same as the pressure inside the arteries.

There are two numbers measured for blood pressure. Systolic blood pressure is the pressure when your heart beats. Diastolic pressure is when the heart relaxes between beats and the pressure drops. Together, they are written as systolic over diastolic pressure. For instance, a blood pressure of 120/80 mm Hg (millimeters of mercury) corresponds to a systolic pressure of 120 and a diastolic pressure of 80.

Using a sphygmomanometer is still considered the best method but, more commonly, devices that combine a blood pressure cuff with electronic sensors are used to measure blood pressure. Another method is to have you wear a device that monitors and records the blood pressure at regular intervals during the day to evaluate your blood pressure over time. This is especially helpful during the diagnostic process and can help rule out “white coat” hypertension, the high measurements that can occur when you are at the doctor’s office and not at other times.

A single measurement of blood pressure is not enough to diagnose hypertension. Typically, multiple readings are taken on different days. A diagnosis of high blood pressure is made if measurements are consistently high.

What is normal blood pressure?

Guidelines on “normal” blood pressure differ. Read the article on Hypertension to find out what your blood pressure readings may mean.

Risk Factors

Some risk factors are related to things you can’t change, such as:

  • African American descent
  • A family history of high blood pressure
  • Older age

Others are lifestyle factors that are under your control including:

  • Being overweight or obese
  • Not getting enough exercise
  • Smoking
  • Heavy alcohol drinking
  • A diet high in salt

Sometimes medication, illegal drug use, or underlying conditions such as diabetes, kidney disease or thyroid disease, can cause hypertension. This is called secondary hypertension and treating these conditions, or stopping the medication, may remove the underlying cause of high blood pressure.

Screening Recommendations

The 2017 American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines recommends annual screening for adults with blood pressure less than 120/80 mm Hg.

  • If you have higher blood pressure and are otherwise at low risk for cardiovascular disease, the guidelines recommend re-screening in 3-6 months after the initial high reading. (For details, read Hypertension)
  • If you have hypertension, and are at high risk for cardiovascular disease, more frequent screenings are necessary, according to your heart disease risk and your blood pressure readings. Treatment with anti-hypertension drugs is likely necessary in these cases.

The U.S. Preventive Services Task Force (USPSTF), along with the American Academy of Family Physicians, recommends screening every 3 to 5 years for adults 18 to 39 years old with normal blood pressure (less than 130/85 mm Hg), who do not have other risk factors.

  • Adults older than age 40, or those at increased risk for high blood pressure, should be screened every year. The USPSTF considers people who have high-normal blood pressure (130 to 139/85 to 89 mm Hg), those who are overweight or obese, or are African American to be at increased risk.
  • The USPSTF also recommends confirming high blood pressure measurements outside of an office setting, with repeated measurements before diagnosis and treatment.

Related Content

Conditions: Hypertension

Sources (Last Reviewed 4/17/19)

(2017 August 28). Young adults, especially men, fall behind in high blood pressure treatment and control. American Heart Association. Available online at: Accessed February 2019.

(Reviewed 2014 July 7). Family History and Other Characteristics That Increase Risk for High Blood Pressure. Centers for Disease Control and Prevention. Available online at Accessed February 2019.

(2016 October 31). What is high blood pressure? American Heart Association. Available online at Accessed February 2019.

(Reviewed 2017 November 13). Monitoring your blood pressure at home. American Heart Association. Available online at Accessed February 2019.

(Reviewed 2017 November 30). Monitor your blood pressure. American Heart Association. Available online at Accessed February 2019.

(Reviewed 2017 November 30). Understanding blood pressure readings. American Heart Association. Available online at Accessed February 2019.

(2019 February 13). High blood pressure. Centers for Disease Control and Prevention. Available online at Accessed February 2019.

Heart health screenings. American Heart Association. Available online at Accessed February 2019.

Highlights from the 2017 guideline for the prevention, detection, evaluation and management of high blood pressure in adults. American Heart Association. Available online at Accessed February 2019.

High blood pressure. National Heart, Lung, and Blood Institute. Available online at Accessed February 2019.

Breast Cancer

Breast cancer is the second most commonly diagnosed cancer in American women and a leading cause of cancer death. Almost 70% of breast cancers are found in women 55 or older and about 10% are found in women younger than 45. Regular screening can help to detect tumors at an early stage when they are most treatable. Mammography is an imaging test that can detect breast cancer before symptoms develop.

The medical community recognizes the value of breast cancer screening and mammography, but there are some differences in the advice on how often it should be done and when it should be started. Most organizations agree that women should work with their healthcare provider to assess their personal risk of developing breast cancer and determine what is best for them. Considerations can be given to the benefits of screening as well as the harms. While screening can detect cancer early when it is most treatable, it may also lead to false-positive results and unnecessary follow-up procedures, such as biopsies.

Recommendations for average-risk women:

Women with average risk have no personal or family history of breast cancer and no other risk factors for breast cancer.

Clinical Breast Exams

  • The American College of Obstetricians and Gynecologists (ACOG) and the National Comprehensive Cancer Network (NCCN) say women may be offered a clinical breast exam by a healthcare professional every 1 to 3 years for women ages 25 to 39 as part of their regular health exam and annually for women age 40 and older.
  • The U.S. Preventive Service Task Force (USPSTF) and the American Cancer Society (ACS) state that there is insufficient evidence or that they do not recommend clinical breast examinations for women at any age.

Breast self-awareness is important, according to ACOG. Women of all ages should discuss breast self-awareness with their healthcare provider and immediately report any change in their breasts’ normal appearance and feel. These changes could include pain, a mass, nipple discharge other than breast milk, or redness.


  • Mammograms are generally not recommended for women younger than age 40 with no known risk factors.
  • ACS says that women aged 40 to 44 have the option to begin breast cancer screening with mammograms and recommends that women aged 45 to 54 have a mammogram every year.
  • ACOG, USPSTF and the American College of Physicians (ACP) say that women aged 40 to 49 should be offered screening and should discuss the benefits and harms of screening mammography with a healthcare practitioner. The decision when to start regular screening mammography should be an individual one, taking into consideration such factors as a woman’s risk tolerance. If a woman chooses screening, ACOG recommends it every 1 to 2 years and USPSTF and ACP say it should be done every 2 years.

Increased Risk

Family history and genetics can contribute to a high lifetime risk. Other risk factors for breast cancer include, for example, a personal history of breast cancer, obesity, beginning your period at a younger age, having your first child after age 35, never giving birth, postmenopausal hormone therapy, beginning menopause at an older age, and alcohol consumption.

ACS recommends that women at high lifetime risk be screened with magnetic resonance imaging (MRI) in addition to mammography annually beginning at age 30 and continuing as long as they are in good health.

Some of the important factors contributing to a high lifetime risk include:

  • Carrying a mutated BRCA1 or BRCA2 gene or having a close relative with the gene
  • Having had chest radiation at a young age (between 10 and 30 years old)
  • Certain family histories, such as multiple close relatives with breast or ovarian cancer

If you suspect you are at an increased risk for breast cancer, you should consult your healthcare provider and consider developing an individualized screening program.

American Cancer Society: Breast Cancer Risk and Prevention
National Cancer Institute: Breast Cancer Screening

Sources Used in Current Review (last reviewed 2/2/19)

(September 11, 2018) Centers for Disease Control and Prevention. Breast cancer: What is breast cancer screening? Available online at Accessed on January 2019.

(September 10, 2018) National Institutes of Health, National Cancer Institute. Surveillance, Epidemiology, and End Results Program. Cancer stat facts: Female breast cancer. Available online at Accessed January 2019.

(July, 2017) American College of Obstetricians and Gynecologists (ACOG). ACOG Practice Bulletin. Clinical management guidelines for obstetrician-gynecologists. Available online at Accessed January 2019.

(January, 2016) U.S. Preventative Services Task Force. Breast cancer: Screening. Available online at Accessed on January 2019.

(January, 2016) Facing Our Risk of Cancer Empowered. Comparison of breast cancer screening guidelines. Available online at Accessed on January 2019.

Oeffinger K.C., et al. American Cancer Society. Breast cancer screening for women at average risk: 2015 guideline update from the American Cancer Society. 2015;314:1599-614. Journal of the American Medical Association. Available online at Accessed on January 2019.

(October 9, 2017). ACS. Breast cancer early detection and diagnosis. Available online at Accessed on January 2019.

(May 18, 2018) National Comprehensive Cancer Network. Clinical Practice Guidelines in Oncology. Breast cancer screening and diagnosis. Available online at Accessed on January 2019.

Cervical Cancer

Cervical cancer is caused by the uncontrolled growth of cells in the cervix, the narrow bottom portion of a woman’s uterus. Cervical cancer is slow-growing and can take several years to develop. According to the American Cancer Society, cervical cancer is diagnosed most often in women between the ages of 35 and 44 years old. The average age at diagnosis is 50 years old. Cervical cancer is rarely diagnosed in women younger than age 20.

Almost all cervical cancers are caused by persistent infections with specific types of human papillomavirus (HPV). Two high-risk HPV types, 16 and 18, cause 80% of all cervical cancers. Cervical cancers caused by 9 high-risk types of HPV can be prevented with vaccination starting at age 11 to 12.

HPV is a very common sexually transmitted disease. Many HPV infections resolve without treatment—the body is able to clear the infection—but infections with high-risk HPV types that do not go away can lead to cervical cancer. It can take many years for an HPV infection to develop into cancer. A persistent infection with high-risk HPV can cause infected cells to grow uncontrollably. Usually the immune system recognizes these cells and limits their growth, but sometimes the cells remain and become precancerous.

Most deaths from cervical cancer can be avoided by having regular checkups and cervical cancer screens. Routine screening can help identify cervical cancer early, at a time when it is highly curable. Screening even finds precancerous lesions that can be monitored or removed before cancer starts to develop.


Cervical cancer screening tests include:

  • Pap smear (Pap test)—this test screens for precancerous or cancerous changes in cervical cells. A sample of cervical cells is placed on a slide, treated with a dye, and examined using a microscope.
  • HPV test—this test detects the genetic material (DNA or messenger RNA) of high-risk HPV (hrHPV) in a sample of cervical cells.

Recommendations from the U.S. Preventive Services Task Force (USPSTF) for cervical cancer screening have been endorsed by the Society of Gynecologic Oncology and the American Society for Colposcopy and Cervical Pathology (ASCCP) and are largely in line with current guidelines from the American College of Obstetricians and Gynecologists (ACOG), ASCCP, the American Cancer Society, and the American Society for Clinical Pathology (ASCP).

These health organizations recommend that women ages 30 to 65 choose one of the following screening strategies. Talk to your healthcare provider about the pros and cons of all three screening strategies so you can decide which approach is best for you:

  • Co-testing with a Pap smear and high-risk HPV (hrHPV) test every 5 years, or
  • Pap smear alone every 3 years, or
  • hrHPV tests alone every 5 years (considered an alternative screening strategy)

More frequent screening is advised for women with risk factors, such as:

  • Being exposed to a drug called DES (a drug given to some women between 1940 and 1971 to prevent miscarriage) before birth. In this case, a Pap smear is required for screening.
  • A previous abnormal cervical cancer screening or diagnosis of cervical cancer
  • Family history of cervical cancer
  • History of chlamydia infections
  • compromised immune system (e.g., HIV infection)

(See the section on Risk Factors in the Cervical Cancer article.)

You should still undergo regular cervical cancer screening even if you have been vaccinated against HPV.

For women with hysterectomies
If you have had a total hysterectomy (surgical removal of the uterus and cervix) and you have no history of cervical cancer or cervical changes, guidelines suggest that you may discontinue cervical cancer screenings. However, if you have a history of cervical cancer or severe to moderate cervical changes, then it is recommended that you continue to be screened for cervical cancer for 20 years after your surgery. If you had a partial hysterectomy (removal of the uterus but not the cervix), then you should continue to have regular cervical cancer screenings as recommended above.

Even if you do not need cervical cancer screening each year, an annual well-woman exam is still recommended for most women, reminds ACOG.

National Cancer Institute: Cervical Cancer Screening (PDQ®)–Patient Version

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(November 20, 2016) American Cancer Society. The American Cancer Society guidelines for the prevention and early detection of cervical cancer. Available online at Accessed June 2020.

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(February 18, 2014) American Cancer Society. DES Exposure: Questions and Answers. Available online at Accessed June 2020.

Colon Cancer

Colon cancer is the uncontrolled growth of abnormal cells within the layers of tissue that line the colon. It is the third most common, non-skin cancer in adults and the third leading cause of cancer deaths in men and women in the United States. The lifetime risk of developing colon cancer is about 1 in 21 (or 4.7%) for men and 1 in 23 (4.4%) for women, according to the American Cancer Society (ACS).

The incidence of colon cancer has decreased over the last several years in people age 55 and older due in part to screening tests that have resulted in the removal of cancerous and precancerous polyps. However, there has been a 51% increase in colon cancer among people younger than age 50 since 1994. As a result, the ACS and the U.S. Preventive Services Task Force lowered their recommended starting age for colon cancer screening to age 45 for people with an average risk of colon cancer.

Furthermore, if you have one or more risk factors for colon cancer you should talk to your healthcare practitioner who can help you assess your individual risk factors and determine if you should begin screening at a younger age and more frequently. As the Centers for Disease Control and Prevention (CDC) notes, any of the recommended tests is better than no test.

Screening Recommendations

Several health organizations have colon cancer screening recommendations. In 2017, screening guidelines for the early detection of pre-cancerous polyps and colon cancer were released by the US Multi-Society Task Force (MSTF) on Colorectal Cancer. The USPSTF released updated recommendations in 2021 and the American Cancer Society (ACS) updated their guidelines in 2018. While these groups may differ on which tests to use and how often, they each support screening for colon cancer. Recommendations are based on your age and level of risk.

Increased and High Risk: 
Risk of colon cancer increases with age, being overweight or obese, and with the occurrence of cancers in other parts of the body. Examples of other risk factors include:

  • Family history—having one or more family members with colon cancer or multiple polyps, especially if they were younger than age 60 at diagnosis
  • Diet—high fat and meat diets are risk factors, especially combined with not eating enough fruits, vegetables, and/or high-fiber foods
  • Lifestyle—these risk factors include cigarette smoking, drinking excessive amounts of alcohol, and lack of regular exercise
  • Having ulcerative colitis, a form of inflammatory bowel disease
  • Having type 2 diabetes
  • Racial or ethnic background—African Americans and Ashkenazi Jews have higher risk and rates of colon cancer compared to others.
  • Having a personal history of colon cancer and/or high risk precancerous polyps
  • Having a rare inherited disease called familial adenomatous polyposis (FAP)—this causes benign polyps to develop early in life and causes cancer in almost all affected persons unless the colon is removed. (See the Genetics Home Reference article on FAP)
  • Having a genetic syndrome called Lynch syndrome (hereditary non-polyposis colon cancer or HNPCC) (See the Genetics Home Reference article on Lynch syndrome.)

People with increased or high risk of colon cancer may be advised to start screening at a younger age (e.g. age 40). A colonoscopy is usually recommended because it is the most accurate and thorough. Also, the recommended screening interval for high-risk individuals is shorter than for people with average risk (such as every 1-2 years compared to every 10 years).

Additionally, people who have been screened and found to have colon cancer or high risk pre-cancerous polyps also need more frequent re-testing, usually at least every 3 years. (This is called surveillance.) For example, the MSTF guidelines advise enhanced surveillance for people with 3-10 small tubular adenomas as well as those with 1 or more high-risk polyps (i.e., villous features, larger than 10 mm diameter tubular adenoma or serrated sessile polyp, or any polyp that has very atypical features, called high grade dysplasia). On the other hand, those with 1-2 small (less than 10 mm) tubular adenomas in the colon can be re-screened at normal intervals (i.e., every 10 years). Another common polyp, termed a hyperplastic polyp, is not felt to increase risk of colon cancer.

For more information on these types of polyps, read the American Cancer Society’s webpage Understanding Your Pathology Report: Colon Polyps

Average Risk

This includes people with no known risk factors other than age. The ACS and the USPSTF recommend that all average-risk people begin screening at age 45. The MSTF recommends that people with average risk for colon cancer begin screening at age 50, and that African-Americans begin at age 45.

Screening Tests 
The following table summarizes the screening tests that are options for people with average risk. Tier 1 tests are the tests of choice, according to the MSTF, while tier 2 tests have some disadvantages compared to tier 1 tests. The ACS guidelines do not prioritize a particular screening test and instead says patients and their healthcare practitioners should choose from among several tests based on the patient’s preference.

Tier 1 tests
Colonoscopy Examination of the rectum and entire colon with a lighted instrument Every 10 years Can examine the entire colon

Detects pre-cancerous polyps and cancer

Can remove polyps and take biopsies for pathological testing

Extensive full bowel preparation ahead of time

Sedation needed to perform

Takes at least one day for prep and recovery

Risk of bleeding, infection or bowel tears

Fecal Immuno-chemical test (FIT) stool test Test to detect hidden blood in stool samples Annually No dietary or drug restrictions

No bowel preparation

No direct risk to bowel

Samples can be collected at home

Cannot detect precancerous changes

May miss some cancers

May need to have colonoscopy if positive result

Tier 2 tests
Flexible sigmoidoscopy Examination of the rectum and lower colon with a rigid or flexible lighted instrument Every 5-10 years Minimal preparation ahead of time

Detects pre-cancerous polyps and cancer

Does not usually need sedation

Fairly quick and safe

Only examines about 30% of colon

Small risk of bleeding, infection or bowel tear

May need to have colonoscopy if abnormal result found

Virtual colonoscopy (CTC, or computed tomographic colonography) Examination of the rectum and entire colon to the small intestine using x-rays and computers; tube inserted in rectum and bowel is inflated with air Every 5 years No sedation required

Can view entire colon

Detects pre-cancerous polyps and cancer

Relatively safe; minimal risk of tear to colon

Full bowel preparation required

May need standard colonoscopy if abnormal results

Effectiveness as a screening tool is not fully accepted

Fecal Immunochemical test (FIT)-DNA Detects blood and mutations in specific genes associated with colon cancer in DNAisolated from a stool sample Every three years, according to the American Cancer Society and MSTF No bowel preparation or dietary restrictions

Sample can be collected at home

No risk of bowel tear

Cannot detect precancerous changes

Not as effective as annual FIT

Adequate stool sample must be obtained

Special handling needed

May need colonoscopy if abnormal result found

Capsule colonoscopy Examination of the colon performed by swallowing an indigestible pill with embedded video cameras Every 5 years per MSTF Detects pre-cancerous polyps and cancer

No sedation required

Relatively safe

May need standard colonoscopy if abnormal results

Not approved by the FDA for screening people at average risk

No Tier recommendation
Guaiac-based fecal occult blood test (gFOBT) stool test Test to detect hidden blood in stool sample Annually No bowel preparation

No direct risk to bowel

Sample can be collected at home

Dietary restrictions before testing

Cannot detect precancerous changes

Detects any blood, not just from cancers but from food or dental procedures

May need colonoscopy if positive result

In addition to screening tests, a healthcare practitioner may perform a digital rectal examination (DRE) to feel for a rectal mass with a gloved finger. Most colon cancers, however, are beyond the detection range of a DRE.

If a test other than colonoscopy gives a result suggestive of polyps or cancer, a colonoscopy is often done to examine the full colon and remove polyps or potentially cancerous areas.

Decision Aids

Because any invasive procedure carries some level of risk, you should talk to your healthcare provider about the screening tests recommended for you. Some employers, health plans, and health practitioners offer decision aids.

Also, don’t neglect the protection of getting re-tested at the interval recommended by your healthcare provider.

Tests: Fecal Occult Blood Test and Fecal Immunochemical Test
Condition: Colon Cancer


(May 18, 2021) Colorectal Cancer: Screening, Final Recommendation Statement. US Preventive Services Task Force. Accessed August 2021.

Rex DK, Boland CR, Dominitz JA, et al. Colorectal Cancer Screening: Recommendations for Physicians and Patients from the U.S. Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol. 2017; 112(7):1016–1030. Available online at Accessed on 9/12/2018.

Canadian Task Force on Preventive Health Care, Recommendations on screening for colorectal cancer in primary care Canadian Med Assoc J. 2016 Mar 15; 188(5): 340–348. Available online at Accessed 9/12/2018

Wolf AMD, Fontham ETH, Church TR, et al. Colorectal cancer screening for average‐risk adults: 2018 guideline update from the American Cancer Society. CA Cancer J Clin. 2018; 68(4):250-281. First published: 30 May 2018 Last accessed 9/12/2018

Prostate Cancer

Prostate cancer is the second most frequently diagnosed cancer in men, after skin cancer. It is also the second leading cause of cancer death, after lung cancer. As many as 1 in 7 American men will develop it during their lifetime, with most cases diagnosed in men 65 years of age or older. Some prostate cancers progress quickly and cause death within months or a few years, but most grow slowly and never pose a major health threat.

Screening for prostate cancer is important for men to discuss with their healthcare providers. Many complicated issues are involved:

  • Current technology cannot tell a slow-growing cancer from a fast one, and the cancer may never significantly affect a man’s health or life expectancy.
  • Screening tests for prostate-specific antigen (PSA) do not detect all cases, and some elevated PSA results do not prove to be cancer.
  • Diagnosis through biopsy (with a small risk of infection and bleeding) and side effects of treatment (which could cause erectile dysfunction and incontinence) can potentially be harmful itself. Most prostate cancers are slow-growing and may not cause any trouble.
  • Results from long-term trials on whether PSA testing improves prostate cancer survival rates have been inconclusive.

Informed decisions
In spite of the questions surrounding prostate cancer screening, most health organizations agree that men should receive balanced information about prostate cancer screening and recommend that men discuss it with their healthcare provider. You need to know the risks, uncertainties, benefits, and limits of prostate cancer testing and treatment and should work with your healthcare provider to understand your options and decide what is best for you. Before choosing prostate screening, you should weigh the pros and cons based on your age, life expectancy, family history, race, overall health, previous test results, and individual risk tolerance.

One important factor to consider is your personal risk of developing prostate cancer:

  • Average risk: Healthy men with no known risk factors
  • Increased risk: African American men or men who have a father or brother who was diagnosed before they were 65
  • High risk: Men with more than one relative who was affected at a young age

If you choose to undergo screening, the following tests may be recommended:

  • Prostate specific antigen (PSA)—blood test that measures the level of PSA in the blood
  • Digital rectal exam (DRE)—part of a physical exam that the health practitioner performs to examine the prostate gland

Most organizations do not recommend prostate cancer screening for men 49 and younger, unless they have increased or high risk. The exception is the National Comprehensive Cancer Network.

  • The National Comprehensive Cancer Network (NCCN) recommends a baseline test at age 45 for men who want screening, which will determine when and how often to have future tests. It advises using the DRE and the PSA test, in combination, for the broadest detection of cancer in its early stages. If the PSA test result is greater than 1.0 ng/mL, or if the man is at a higher risk, it recommends a DRE and PSA test at one- to two-year intervals.
  • The U.S. Preventive Services Task Force (USPSTF) says that for men younger than age 50 at increased risk, including African American men and men with a family history of prostate cancer, a reasonable approach is to discuss the benefits and harms of PSA screening to make an informed decision. The decision is based on the harm that can come from false-positive PSA test results which then may lead to surgical or radiation treatment that may ultimately provide little benefit.
  • The American Cancer Society (ACS) recommends that healthy men with average risk who wish to be screened consider waiting to get tested until age 50. ACS recommends considering earlier testing for higher-risk groups.
    • If you are African American or have a father or brother who was diagnosed before they were 65, ACS recommends considering testing at 45 years of age.
    • If more than one relative was affected at a young age, you could begin testing at 40 years old; then, depending on the results, get tested again at age 45 or earlier as results warrant.
    • ACS recommends re-screening every two years if your PSA level is less than 2.5 ng/mL and annual screening if it is 2.5 ng/mL or higher.
  • The American Urological Association (AUA) recommends waiting to have a baseline PSA and DRE until age 55 for men at average risk who wish to be screened. For those at increased or high risk, AUA advises that decisions regarding prostate cancer screening be individualized based on patient preferences and an informed discussion about benefits and harms.
  • The American College of Physicians advises against screening men younger than age 50.


Articles: Making Informed Decisions for Better Health

Sources Used in Current Review (last reviewed 6/25/2018)

(March 11, 2016) American Cancer Society. About Prostate Cancer. Available online at Accessed on June 22, 2018.

(March 11, 2016) American Cancer Society. Prostate Cancer Risk Factors. Available online at Accessed on June 22, 2018.

(April 14, 2016) American Cancer Society. If Prostate Cancer Screening Test Results Aren’t Normal. Available online at Accessed on June 22, 2018.

(April 14, 2016). American Cancer Society. Recommendations for Prostate Cancer Early Detection. Available online at Accessed on June 22, 2018.

(April 5, 2018) National Comprehensive Cancer Network. Clinical Practice Guidelines in Oncology: Prostate Cancer Early Detection. Available online at Accessed on June 22, 2018.

(May 8, 2018) U.S. Preventive Services Task Force Bulletin. USPSTF Issues Final Recommendation on Screening for Prostate Cancer. Available online at Accessed on June 22, 2018.

(May 2018) U.S. Preventive Services Task Force. Final Recommendation Statement: Prostate Cancer: Screening. Available online at Accessed on June 22, 2018.

(May 5, 2018) American Urological Association. Press release: AUA Responds to USPSTF Final Recommendations on Screening for Prostate Cancer. Available online at Accessed on June 22, 2018.

(2015) American Urological Association. Clinical Guidelines: Early Detection of Prostate Cancer. Available online at Accessed on June 22, 2018.

(19 May 2015) American College of Physicians. Screening for Cancer, Summary for Patients. Available online at Accessed June 2018.

Human Immunodeficiency Virus (HIV)

HIV is the virus that causes AIDS (acquired immunodeficiency syndrome), a life-threatening disease. Initially, an HIV infection may cause no symptoms or cause non-specific, flu-like symptoms that resolve after a short time period. The only way to determine whether a person has been infected is through HIV testing.

If the infection is not detected and treated, eventually symptoms of AIDS emerge and begin to progressively worsen. Without treatment, HIV destroys the immune system over time and leaves a person’s body vulnerable to debilitating infections.

HIV is spread in the following ways:

  • By having sex with an infected partner
  • By sharing needles or syringes (such as with intravenous injection drug abuse)
  • During pregnancy or birth; if a pregnant woman is infected with HIV, the virus can be passed to and infect her developing baby.
  • Through contact with infected blood
  • In the U.S. today, because of screening blood for transfusion and heat-treating techniques and other treatments of blood derivatives, the risk of getting HIV from transfusions is extremely small. However, before donated blood was screened beginning in 1985 in the U.S. and before treatments were introduced to destroy HIV in some blood products, such as factor 8 and albumin, HIV was transmitted through transfusion of contaminated blood or blood components.

Why Get Screening?
Screening for HIV is now part of routine healthcare in the United States and is an important part of wellness and prevention. This is because diagnosis early in the course of infection leads to timely, effective treatment that decreases the risk of progression to AIDS. A major National Institutes of Health (NIH) clinical trial published in 2015 found that individuals with HIV have a lower risk of developing AIDS and other serious illnesses if they start antiretroviral therapy sooner rather than later.

Early diagnosis also has important benefits for others and society at large. Thousands of people are diagnosed with HIV each year, and about 1 in 8 people in the United States with HIV are unaware that they have it. An individual can prevent further disease spread by learning their status, modifying behavior and not exposing others to infected blood or body fluids. Pregnant women who have HIV can start treatment to prevent spreading the disease to their children.

If an HIV screening test shows a person is not infected, he or she can take steps to avoid infection. For individuals who are HIV-negative but at high risk for HIV, the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) recommend that they consider taking pre-exposure prophylaxis (PrEP), a daily pill to help prevent infection. For people taking PrEP consistently, the risk of HIV infection is significantly lower compared to those who did not take it.

Know Your Risk
Several situations put you at high risk of contracting HIV:

  • You’ve had unprotected sex with more than one partner.
  • You have or have had a sexually transmitted disease (STD), which appears to make people more susceptible to and at higher risk for acquiring HIV infection during sex with infected partners.
  • You’re a man who has had sexual contact with another man.
  • You have exchanged sex for money or drugs or had anonymous sex.
  • You use or used injection drugs and are likely to have shared unsterilized needles.
  • You have an HIV-positive sexual partner.
  • You have had sex with anyone who falls into one of the categories listed above or are uncertain about your sexual partner’s risk behaviors.
  • You’ve been diagnosed with or treated for hepatitis or tuberculosis (TB).

How often you are tested should depend on your risk, activities, and sexual contacts. For example, during a long-term, truly monogamous sexual relationship, you may want just one test. However, if you or your partner have had sexual contact with more than one person in recent months, your risk of infection is greater. If you or a person with whom you’ve had sexual contact (even unwanted sexual contact) engaged in some risky behavior, you have even more reason to be tested.

Screening Tests
Different types of tests are available for HIV screening:

  • Combination HIV antibody and HIV antigen test—this is the recommended screening test for HIV. It is available only as a blood test. It detects the HIV antigen called p24 plus antibodies to HIV-1 and HIV-2. (HIV-1 is the most common type found in the United States, while HIV-2 has a higher prevalence in parts of Africa.) By detecting both antibody and antigen, the combination test increases the likelihood that an infection is detected soon after exposure. These tests can detect HIV infections in most people by 2-6 weeks after exposure.
  • HIV antibody testing—all HIV antibody tests used in the U.S. detect HIV-1, and some tests have been developed that can also detect HIV-2. These tests are available as blood tests or tests of oral fluid. HIV antibody tests can detect infections in most people 3-12 weeks after exposure.

Various options are available for getting tested:

  • A blood or oral sample can be collected in a healthcare provider’s office or a local clinic and sent to a laboratory for testing. In these same settings, a rapid test may available in which results are generated in about 20 minutes.
  • A home collection kit approved by the U.S. Food and Drug Administration (FDA) is available for HIV antibody testing. This allows a person to take a sample at home and then mail it to a testing center. Results are available over the phone, along with appropriate counseling.
  • The FDA has approved an HIV test for home use. The testing kit is the same as that used in many healthcare providers’ offices and clinics in which an oral sample is collected for testing and results are available in about 20 minutes. Though the home test is convenient, it has limitations. It is less sensitive than a blood test so the home test may miss some cases of HIV that a blood test would detect and it is not as accurate when it is performed at home by a lay person compared to when it is performed by a trained healthcare professional. Care must be taken to avoid errors when performing the test. (For more, see the article on Home Testing, Avoiding Errors.)

Screening tests have limitations, so it is important to remember that:

  • A negative screening test means only that there is no evidence of disease at the time of the test. If you have increased risk of HIV infection but negative screening results, it is very important to get screening tests on a regular basis.
  • HIV tests will not detect the virus immediately after infection. Still, talk to your healthcare provider immediately if you think you’ve been infected. If exposure to the virus is recent, then antibody levels may be too low to detect. If an initial test is negative, it may be necessary to repeat testing at a later time with another antibody test or combination HIV antibody/antigen test. In the case of a negative result, the CDC recommends retesting three months after likely exposure.
  • A positive screening test is not a diagnosis. A positive result must be followed by a second antibody test that differentiates between HIV-1 and HIV-2 to establish a diagnosis.

For more details on HIV screening, see the article on HIV Antibody and p24 Antigen.

Screening Recommendations

  • The Centers for Disease Control and Prevention (CDC) recommends that everyone 13 to 64 years old have an HIV screening test at least once. The CDC recommends getting tested each year if you’ve engaged in an activity that can put you at increased risk of infection and spreading the disease. Additionally, men who have sexual contact with other men should be tested be tested every three to six months.
  • The United States Preventive Services Task Force (USPSTF) recommends that all teens and adults ages 15 to 65 be screened for HIV infection. It also recommends that younger adolescents and older adults at increased risk undergo screening for HIV. As for how often, the Task Force says a reasonable approach is one-time testing for all people ages 15 to 65 and at least annual screenings for those at very high risk of HIV, such as men who have sex with men, injection drug users, and those who live or receive medical care in areas where the rate of HIV infection is high. Individuals at increased but not very high risk may be screened less frequently than every year. The USPSTF recommends every three to five years as a guideline. The Task Force points out that risk is “on a continuum” and health professionals should use their own discretion in deciding how frequently to test people for HIV.
  • The American College of Physicians agrees with the CDC that everyone aged 13 to 64 be offered an HIV screening test in healthcare settings. It also recommends that healthcare practitioners should determine the frequency of repeat screening on an individual basis.
  • The American Academy of Pediatrics (AAP) recommends targeted HIV screening for all sexually active youth. In addition, the academy advises routine testing starting at age 16 for all teens who live in areas where prevalence is high; that is, where more than 1 in 1,000 individuals are infected.
  • For recommendations specific for pregnant women, see the article on Pregnancy.

Aside from these recommendations, certain individuals should get tested and learn their status. These include:

  • People diagnosed with hepatitis, TB, or an STD
  • People who received a blood transfusion prior to 1985 or had a sexual partner who received a transfusion and later tested positive for HIV
  • A healthcare worker with direct exposure to blood on the job
  • Any individual who thinks he or she may have been exposed

Talk to your healthcare provider
Don’t be surprised if a healthcare practitioner, in any care setting, offers you an HIV screening test, in keeping with CDC recommendations. If your healthcare provider does not bring up sexual health topics, you can simply ask for a test or a risk assessment. You can also use confidential services to obtain testing or counseling.

Resources & Links

For confidential information, you can call the STDs and HIV/AIDS hotline of the CDC: 800-CDC-INFO (232-4636).
To find a testing site near you, visit National HIV and STD Testing Resources HIV and AIDS
MedlinePlus: Screening and diagnosis for HIV
Mayo Clinic: HIV/AIDS – Preparing for your appointment
AIDSinfo: HIV Testing

Sources Used in Current Review

Qaseem, A. et al. (2009 January 20). Screening for HIV in health care settings: A guidance statement from the American College of Physicians and HIV Medicine Association. Annals of Internal Medicine. Available online at Accessed 11/6/2016.

(2011 October 31). The pediatrician’s role in preventing HIV infection. American Academy of Pediatrics. Available online at Accessed 11/6/2016.

(2013 April). Human Immunodeficiency Virus (HIV) infection: Screening. U.S. Preventive Services Task Force. Available online at Accessed 11/6/2016.

(2015 May 27). Press release: Starting antiretroviral treatment early improves outcomes for HIV-infected individuals. National Institutes of Health. Available online at Accessed 11/6/2016.

(Updated 2016 January 22). Working in healthcare and HIV. AVERT. Available online at Accessed 11/6/2016.

(2016 May 23). Recommendations for HIV prevention with adults and adolescents with HIV. Centers for Disease Control and Prevention. Available online at Accessed 11/6/2016.

(2016 October 27). HIV and AIDS: Testing. Centers for Disease Control and Prevention. Available online at Accessed 11/6/2016.

(2016 June 20). HIV testing. Centers for Disease Control and Prevention. Available online at Accessed 11/6/2016.

Chlamydia and Gonorrhea

Chlamydia and gonorrhea are the most common bacterial sexually transmitted diseases (STDs) in the United States today, but many infected people have no symptoms. These infections usually affect the genitals but may also cause infections of other areas, such as the throat and rectum. Pregnant women may transmit the infections to their newborns. Left untreated, these diseases can cause infertility and other health complications. However, both diseases can be cured with antibiotics.

While rates of chlamydia and gonorrhea are highest in younger people, any sexually active person can get a chlamydia or gonorrhea infection. Many people have both chlamydia and gonorrhea infections at the same time.

Recommendations for Women

The U.S. Centers for Disease Control and Prevention (CDC), the U.S. Preventive Services Task Force (USPSTF), the American Academy of Family of Physicians (AAFP), and the American College of Obstetricians and Gynecologists (ACOG) recommend chlamydia and gonorrhea screening for all sexually active adult women who have risk factors, such as having a new or multiple sex partners. The CDC specifically recommends annual screening for those at risk.

For screening recommendations during pregnancy, see Pregnancy & Prenatal Testing.

Recommendations for Men

These organizations do not recommend routine screening for healthy, sexually active, heterosexual men. Health care providers may, however, use their judgment and consider risks, such as prevalence in the community. It is important to remember that an infected male can spread these diseases and even re-infect a partner if he does not complete treatment. For sexually active men who have sex with men, the CDC recommends chlamydia and gonorrhea screening at least annually.


Examples of risk factors include:

  • Previous chlamydia or gonorrhea infections, even if you were treated
  • Having other STDs, especially HIV
  • Having new or multiple sex partners
  • Using condoms inconsistently
  • Exchanging sex for money or drugs
  • Using illegal drugs
  • Living in a detention facility

Because reinfection rates are high, the CDC recommends that both women and men who are treated for chlamydia or gonorrhea infection be retested approximately 3 months after treatment or at their next health care visit, regardless of whether they believe that their sex partners were treated. It is important to continue annual screening for these diseases because reinfection is always possible.


CDC: Get Tested, Find Free, Fast, and Confidential Testing Near You

Sources Used in Current Review (last reviewed 12/5/2017)

(2016 October 17, Updated). Chlamydia – CDC Fact Sheet (Detailed). Centers for Disease Control and Prevention. Available online at Accessed on October 2017.

(2016 October 28, Updated). Gonorrhea – CDC Fact Sheet (Detailed Version). Centers for Disease Control and Prevention. Available online at Accessed on October 2017.

(2016 December). Chlamydia, Gonorrhea, and Syphilis FAQ. American Congress of Obstetricians and Gynecologists. Available online at Accessed on October 2017.

Fisher, M. and Schlaberg, R. (2017 July, Updated). Sexually Transmitted Infections. ARUP Consult. Available online at Accessed on October 2017.

(December 1, 2016) Centers for Disease Control and Prevention, STD Risk and Oral Sex – CDC Fact Sheet. Available online at Accessed on October 2017.

(September 2014) US Preventive Services Task Force, Final Recommendation Statement Chlamydia and Gonorrhea: Screening. Available online at Accessed on October 2017.


Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis bacteria. TB primarily targets the lungs but may affect any area of the body. It can be spread through the air from person to person through droplets of respiratory secretions such as sputum or aerosols released by coughing, sneezing, laughing, or breathing.

Most people who become infected with M. tuberculosis manage to confine the mycobacteria to a few cells in their lungs, where they stay alive but in an inactive form. This latent TB infection does not make the person sick or infectious and, in most cases, it does not progress to active tuberculosis. However, some people – especially those with compromised immune systems – may progress directly from initial TB infection to active tuberculosis. People who have HIV are much more likely to become sick if they contract TB. A person who has latent TB and their immune system becomes weakened may then develop active TB. Another increasing concern is drug-resistant forms of TB that are resistant to the antibiotics typically prescribed to treat the disease.

TB is one of the world’s deadliest diseases, although it is relatively uncommon in the U.S. Still, it is a large health issue among at-risk groups. Current guidelines call for targeted screening among such groups.

At Risk

  • People who have close contact with a person who has known or suspected TB disease
  • People with weakened immune systems such as resulting from HIV infection, malnutrition, advanced age, or substance abuse including alcohol and drugs
  • Immigrants from countries with a high rate of TB disease (many countries in Latin America, Africa, Asia, Eastern Europe, and Russia)
  • Medically underserved people, such as those from a low-income environment
  • Residents of long-term care facilities (such as nursing homes, mental health facilities, prisons, AIDS care facilities, and homeless shelters)
  • People who live in unclean or crowded environments and/or without a healthy diet
  • Healthcare workers who work in any of the above situations or with patients who are at increased risk
  • Laboratorians who work with specimens that may contain TB or with TB cultures


The U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Preventive Services Task Force (USPSTF) recommend use of TB tests to identify people who will likely benefit from treatment, including those at increased risk for M. tuberculosis infection or for progression to active TB if they are infected. There are two types of tests that might be performed:

  • IGRA TB blood test (preferred): also known as interferon gamma release assay, requires a blood sample to be drawn.
  • Tuberculin skin test (TST) also called the Mantoux tuberculin skin test, the TST (or PPD for Purified Protein Derivative) is performed by injecting a small amount of fluid (called tuberculin) into the skin in the lower part of the arm. Following this test, you must return within 48 to 72 hours for a trained healthcare worker to measure the reaction and determine if it indicates exposure to M. tuberculosis.

CDC: Tuberculosis (TB)

Sources Used in Current Review

Screening for Latent Tuberculosis Infection in Adults. US Preventive Services Task Force Recommendation Statement. JAMA. 2016;316(9):962-969. doi:10.1001/jama.2016.11046. Available online at Accessed October 2016.

U.S. Centers for Disease Control and Prevention. TB Testing & Diagnosis. Available online at Accessed October 2016.

Hepatitis B

According to the Centers for Disease Control and Prevention (CDC), approximately 850,000 to 2.2 million people in this country have chronic infection with hepatitis B virus (HBV). Many of these people are unaware that they are infected.

HBV is one of five “hepatitis viruses” identified so far that are known to mainly infect the liver. It is spread through contact with blood or other body fluids from an infected person, such as during sex or by sharing needles, razors or toothbrushes, and can also be passed from an infected mother to her baby during or after birth.

HBV infection can be acute or chronic, with the course of infection varying from a mild form that lasts only a few weeks to a more serious form lasting years that can lead to complications such as cirrhosis or liver cancer. According to the CDC, approximately 1,800 people die every year in the U.S. from HBV-related liver disease.

The vast majority of those with chronic infections will have no symptoms. A test for hepatitis B surface antigen (HBsAg) may be used for screening asymptomatic people who fall into one of the high-risk categories for chronic HBV. Effective vaccines against HBV are available; however, those who have not been vaccinated or who are at high risk and were vaccinated before being screened for HBV infection may want to consider getting tested.

Since the prevalence of HBV infection is low in the general U.S. population and most of those infected do not develop complications, HBV screening is not recommended for those who are not at increased risk.

For people with increased risk of infection, several health organizations including the CDC, the American Association for the Study of Liver Diseases (AASLD) and the United States Preventive Services Task Force recommend screening for HBV. Examples of people at risk include:

  • Healthcare and public safety workers with possible exposure to infected blood or other body fluids
  • People born in areas of the world that have a greater than 2% prevalence of HBV (for example, much of Asia and Africa), regardless of whether they have been vaccinated
  • People born in the U.S. but who were not vaccinated early in life and whose parents are from an area with greater than 8% prevalence of HBV
  • Men who have sex with men
  • Injection drug users
  • People who have elevated liver enzymes (ALT and AST) with no known cause
  • People with certain medical conditions that require that their immune system be suppressed, such as organ transplant recipients
  • Dialysis patients
  • People who are in close contact with someone infected with HBV or who have a sexual partner with HBV (i.e. have tested positive for HBsAg)
  • Those infected with HIV
  • People who were vaccinated for HBV after they had already begun high-risk behavior (e.g., men who have sex with men and injection drug users)

In addition, the AASLD recommends HBV screening for:

  • People with multiple sex partners
  • Those who have a history of sexually transmitted diseases (STDs)
  • Prison inmates
  • People with hepatitis C infection

Recommendations for HBV screening during pregnancy are addressed separately. For more information, read the Pregnancy article.

Why get tested?
People with chronic HBV can unknowingly spread the infection to others and remain at risk for serious complications of the infection.

Related Content
Tests: Hepatitis B Testing
Conditions: Hepatitis

Sources Used in Current Review (last reviewed 10/11/17)

LeFevre, M. (2014 July 1). Screening for Hepatitis B Virus Infection in Nonpregnant Adolescents and Adults: U.S. Preventive Services Task Force Recommendation Statement. Annals of Internal Medicine V 161 (1). Available online at Accessed on 8/06/17.

(2016 May 23, Updated). Hepatitis B FAQs for the Public. Centers for Disease Control and Prevention. Available online at Accessed on 8/06/17.

(2015 March). Guidelines for the Prevention, Care and Treatment of Persons with Chronic Hepatitis B Infection. World Health Organization. Available online at Accessed on 8/06/17.

(2017 May 11 Updated). Viral Hepatitis. Centers for Disease Control and Prevention. Available online at Accessed on 8/06/17.

(2016 August 4, Updated). Hepatitis B FAQs for Health Professionals. Centers for Disease Control and Prevention. Available online at Accessed on 8/06/17.

Hillyard, D. and Slev, P. (2017 July Updated). Hepatitis B Virus – HBV. ARUP Consult. Available online at Accessed on 8/06/17.

Workowski, K. and Bolan, G. (2015). Sexually Transmitted Diseases Treatment Guidelines, 2015. MMWR June 5, 2015 / 64(RR3);1-137. Available online at Accessed on 8/06/17.

Hepatitis C

The number of new cases of hepatitis C has increased dramatically since 2010, particularly in young adults, and most have been linked to injection drug use, according to the Centers for Disease Control and Prevention (CDC). For some people, infection with the hepatitis C virus (HCV) is a short-term illness, usually with few, mild symptoms or no symptoms, and the virus is cleared from the body without specific treatment. This is called acute hepatitis C.

However, more than half of people with acute hepatitis C go on to develop chronic hepatitis C. Without treatment, chronic hepatitis C can lead to serious, long-term health problems like cirrhosis and liver cancer, and may be fatal. Chronic hepatitis C progresses slowly over time, so infected individuals may not be aware they have the condition until it causes enough liver damage to affect liver function.

According to the CDC, there are over 2.4 million Americans living with chronic HCV infection and many of these people don’t know it.


You may be at risk of HCV infection if there’s a chance you are exposed to the virus. Hepatitis C is spread most often by exposure to contaminated blood through sharing of needles, syringes or similar equipment used during intravenous (IV) drug abuse. Less commonly, transmission can also occur through sexual activity, sharing personal items like razors or toothbrushes, and from an infected mother to her baby during pregnancy and childbirth. Prior to 1992, when HCV screening of donated blood became routine, it was also possible to become infected with HCV through blood transfusion or organ transplant. Healthcare workers who have been exposed to infected blood (e.g., needlestick injuries) are also at risk.

Screening Recommendations

Health organizations including the CDC, Infectious Diseases Society of America, and the American Association for the Study of Liver Diseases recommend:

  • One-time testing of all people age 18 years and older, regardless of their risk factors for hepatitis C
  • One-time testing of people regardless of age who:
    • Have ever injected illegal drugs
    • Received a blood transfusion or organ transplant prior to July 1992 (before blood and organs were tested for HCV)
    • Have received clotting factor concentrates produced before 1987
    • Were ever on long-term dialysis
    • Are children born to HCV-positive mothers
    • Have been exposed to the blood of someone with hepatitis C
    • Are healthcare, emergency medicine, or public safety workers who had exposure to HCV-positive blood
    • Have evidence of chronic liver disease
    • Have HIV
  • Periodic testing for those with ongoing risk factors, such as injection drug use

The CDC also recommends:

  • Screening of all pregnant women during each pregnancy
  • Screening for any person who requests it

The United States Preventive Services Task Force (USPSTF) similarly recommends:

  • One-time testing for all adults between the ages of 18 and 79 years
  • Regular screening for people at high risk, regardless of age
  • Screening of pregnant women, regardless of age

HCV tests

  • The initial screening test is an HCV antibody test that detects the presence of antibodies to the virus in your blood. Your body produces these antibodies when you are exposed to the virus. This test cannot distinguish a past infection that has cleared and a current, active infection.
  • If the antibody test is positive, a second test for the virus (HCV RNA) is performed to determine whether you have an active, current infection.

For more details, see the article on Hepatitis C Testing.

Why get screening?

Many people who may have contracted the virus, sometimes several years ago, have no noticeable symptoms and are unaware of their condition. A one-time test could detect these infections, allowing for treatment and prevention of complications.

Complications, such as cirrhosis, liver cancer and death, are preventable if chronic hepatitis C is detected and treated before the scarring in the liver is severe. Treatments for HCV can cure over 90% of cases before late complications occur.

CDC: Hepatitis C Questions and Answers for the Public

Sources Used in Current Review (last reviewed July 2020)

(2020 April 29, Reviewed). Testing Recommendations for Hepatitis C Virus Infection. CDC Recommendations for Hepatitis C Screening Among Adults in the United States. Centers for Disease Control and Prevention. Available online at Accessed on 05/23/2020.

(2020 March 2, Updated). Hepatitis C Virus Infection in Adolescents and Adults: Screening. US Preventive Services Task Force. Available online at Accessed on 05/23/2020.

(2020 April 9, Reviewed). Dramatic increases in hepatitis C, CDC now recommends hepatitis C testing for all adults. Centers for Disease Control and Prevention VitalSigns. Available online at Accessed on 05/23/2020.

(2020 May 27, Reviewed). Hepatitis C Questions and Answers for Health Professionals. Centers for Disease Control and Prevention. Available online at Accessed on 05/23/2020.

(2019 November 6, Updated). HCV Guidance: Recommendations for Testing, Managing, and Treating Hepatitis C. AASLD and IDSA. Available online at Accessed on 05/23/2020.

View Sources

Centers for Disease Control and Prevention. CDC Prevention Checklist. Available online at Accessed Oct 2016.

MedlinePlus Medical Encyclopedia. Physical exam frequency. Available online at Accessed Oct 2016.

U.S. Preventive Services Task Force. Published Recomendations. Available online at Accessed Oct 2016.