STD testing: What to know before your appointment

If you're sexually active, particularly with multiple partners, you've probably heard the following advice many times: Use protection and make sure you get tested.

But what does routine sexually transmitted disease (STD) testing really involve? Not all doctors or clinics test for the same STDs. And for some STDs, including genital herpes and human papillomavirus (HPV), there's no practical way to screen everyone, so testing is usually limited to high-risk groups and people with signs and symptoms of particular STDs. Even if you ask your doctor to test you for everything, you can't know for certain that you or your partner will be screened for or clear of all STDs.

Not having sex (abstinence) is the only surefire way to fully protect yourself against an STD. However, if you've decided to be sexually active and you're not in a long-term mutually monogamous relationship with an uninfected partner, plan on routine STD testing to stay healthy. Learn what kinds of STD tests are important and how to ensure you get them.

Routine STD testing

For women
At a minimum, get a Pap test — a simple procedure that collects cells from your cervix to test for cancer or precancerous changes. Cervical cancer can arise as a result of HPV infection — a common STD.

Pap tests are recommended for women who are age 21 and older or no later than three years after a woman's first intercourse. If you're between age 30 and 69 and you've had the same sex partner and normal Pap tests for the past three years, you can probably have less frequent Pap tests — every two to three years.

Routine testing for chlamydia also is recommended for women under age 25.

For men
Centers for Disease Control and Prevention (CDC) guidelines don't suggest routine STD testing if you don't have any symptoms, unless your sexual practices include having sex with men.

If you're a man who has sex with men, annual testing for HIV, syphilis, chlamydia and gonorrhea is recommended. HIV and syphilis can be life-threatening if untreated, and chlamydia and gonorrhea can put you at greater risk of acquiring HIV and other STDs.

For men and women
See your doctor for STD testing if you have any signs of an STD, such as:

• Genital sores, including fluid-filled blisters, ulcerations or warts
• Unusual discharge from your penis or vagina
• Abdominal pain or fever along with unusual vaginal discharge in women, which may indicate pelvic inflammatory disease (PID)

The CDC also encourages HIV testing, at least once, as a routine part of medical care if you're an adolescent or adult between the ages of 13 to 64. The CDC advises yearly HIV testing if you are at high risk of infection — for example, if you've had unprotected sex with more than one sexual partner since your last test.

Ask for STD testing if you think you need it
Don't assume that you're receiving STD testing every time you have a gynecologic exam or Pap test. If you think you need STD testing, request it from your doctor. Talk to your doctor about your concerns and what tests you'd like or need.

Testing for specific STDs

Here are some guidelines for STD testing for specific sexually transmitted diseases.

Gonorrhea and chlamydia
Get screened annually if:

• You're a sexually active girl or woman under age 25
• You're a woman older than 25 and at risk of STDs — for example, if you're having sex with a new partner or multiple partners
• You're a man who has sex with men

If untreated, gonorrhea and chlamydia in women can cause PID, a condition that can lead to infertility. These infections can also significantly increase your risk of acquiring other STDs such as HIV.

Gonorrhea and chlamydia screening is done either through a urine test or through a swab inside the penis in men or from the inside of the cervix in women. The sample is then analyzed in a laboratory. Screening is important, because if you don't have signs or symptoms, you can be unaware that you have either infection.

HIV, syphilis and hepatitis
Request HIV, syphilis and hepatitis testing if you:

• Test positive for gonorrhea or chlamydia, which puts you at greater risk of other STDs
• Have had more than one sexual partner since your last test
• Use intravenous (IV) drugs
• Are a man who has sex with men
• Are concerned you've been exposed

Your doctor tests you for syphilis by taking either a blood sample or a swab from any genital sores you might have. The sample is examined in a laboratory. A blood sample is taken to test for HIV and hepatitis A and B.

It's possible that you may test negative for HIV, syphilis or hepatitis if you've recently acquired the infection. Tests for these infections work by detecting antibodies your immune system produces in response to specific viruses and similar agents. Because the immune response to some infections remains undetectable for several weeks, you may need to be rescreened at a later date.

Getting vaccinated for hepatitis A and B can prevent these infections.

Genital herpes
No good screening test exists for herpes, a viral infection that can be transmitted even when a person doesn't have symptoms.

Your doctor may take a tissue scraping or culture of blisters or early ulcers, if you have them, for examination in a laboratory. But a negative test doesn't rule out herpes as a cause for genital ulcerations.

A blood test also may help detect a herpes infection, but results aren't always conclusive. You may ask for a "type-specific" IgG blood test, which differentiates between the two types of the herpes virus, measuring antibodies to the viruses in your blood. Type 1 is the virus that more typically causes cold sores, although it can also cause genital sores. Type 2 is the virus that more typically causes genital sores. Still, the results may not be totally clear, depending on the sensitivity of the test and the stage of the infection. False-positive and false-negative results are possible.

HPV
Being infected with certain types of human papillomavirus (HPV) is the most important risk factor for developing cervical cancer.

No HPV screening test is available for men, in whom the infection is diagnosed only by visual inspection or biopsy of genital warts that don't appear in every case. In women, HPV testing involves:

• Pap test, once a year if you're younger than age 30 or every three years if you're age 30 or older and have had normal test results your past three tests
• DNA test of the HPV virus, in combination with a Pap test, if you're over age 30

The HPV test is collected with a brushing from the cervical canal. Women with both a negative Pap test and a negative HPV DNA test are at low risk of developing significant precancerous changes of the cervix over the next three years.

The combination of Pap test and HPV DNA testing is not approved by the Food and Drug Administration (FDA) for women younger than 30 because HPV infections that will ultimately clear up on their own are more common in this age group, and a positive test result may lead to unnecessary additional testing and treatment.

The HPV DNA test can test for both low-risk types of HPV, which may cause genital warts, and high-risk types that may cause cervical cancer. Your doctor may recommend testing only for the high-risk types because of their threat to your health. Since no treatments exist for HPV itself — although treatments do exist for genital wart outbreaks caused by HPV — paying for a test to find the low-risk types may be of little use to you.

Girls and women ages 9 to 26 can help prevent HPV infection by receiving the HPV vaccine.

At-home STD testing

Gaining acceptance and popularity are at-home test kits for certain STDs, such as chlamydia and gonorrhea. For home STD testing, you collect a urine sample or a genital or rectal swab and then send it to a laboratory for analysis. Some tests require both types of samples. You can usually get test results in a few days, and you're able to collect the sample in the privacy of your home without need for a pelvic exam or office visit.

However, tests done on samples you collect yourself may have a higher rate of false-positive results, meaning the test indicates you have an STD that you really don't have. If you test positive from a home test, contact your doctor or a public health clinic to confirm the test results.

Positive test results

If you test positive for an STD, the next step is to consider further testing and then to get treatment as recommended by your doctor. In addition, inform your sex partners. Your partners need to be evaluated and treated, because you can pass some infections back and forth.

Expect to feel various emotions. You may feel ashamed, angry or afraid. It may help to remind yourself that you've done the right thing by getting tested so that you can inform your partners and get treated. Talk with your doctor about your concerns.

Before having sex with a new partner

If you can't trust a partner not to give you an STD, you may not want to have sex with that person. You can ask them to be tested for gonorrhea, chlamydia, HIV, syphilis and hepatitis, but negative tests don't guarantee against all STDs.

If you decide to have sex, use condoms. Although they offer only limited protection against herpes, HPV and other infections transmissible without intercourse, condoms do help protect against HIV, chlamydia, syphilis and gonorrhea.