Sexually transmitted diseases (STDs) are infections that are spread by sexual contact with someone who has an STD. STDs are mostly spread through vaginal, anal, or oral sex, and genital touching.

There are about 19 million new STD infections each year in the United States. There are over 20 types of STDs. STDs may be caused by bacteria, parasites, or viruses. STD infection may show a range of signs, or no signs at all. Sometimes people have an STD and don't know it. The only way to know if you have an STD is by a medical exam and testing by your health care provider.

Common STDs caused by bacteria that can be treated and cured with antibiotics include:

• Chlamydia
• Gonorrhea
• Syphilis

Common STDs caused by viruses that can be controlled with treatment include:

• Hepatitis
• Herpes
• HIV
• HPV

If you have an STD, tell current and recent sex partners of the infection.

How do you know if you have an STD?

Your health care provider can examine and test you for STDs. Some women are at a higher risk for STDs. They should have regular exams and testing. Higher risk women include those who:

• Have had a previous STD
• Have new or multiple sexual partners
• Use condoms only some of the time
• Have sex for drugs or money
• Use needles for illegal drugs

Using condoms or not having sex are the best options to protect yourself from STDs.

How can women avoid STDs?

• Avoid sexual contact.
  • Including vaginal, anal, or oral sex, or genital touching.
  • This is the only way to be absolutely sure of avoiding STDs.
• Have safer sex:
  • Reduce the number of sexual partners.
  • Use barriers, including:
    • Male condom
    • Female condom
      • Condoms, when used correctly, can reduce the risk of getting an STD. Each time you have sex use a condom (male or female type):
        • Before vaginal sex
        • Before anal sex
        • Before oral sex
    • Dental dam
    • Plastic wrap, if other barriers are not available
  • Have sex with only one partner who does not have sex with others and does not have an STD.
• Know that washing the vagina or douching after sex will not prevent it.
  • The American Congress of Obstetricians and Gynecologists (ACOG) recommend that women do not douche.
  • Douching can change the balance of germs and acidity in a healthy vagina.
  • Any changes in that balance can cause an over growth of bad bacteria. This can lead to a yeast infection or bacterial vaginosis.
  • If you have a vaginal infection, douching can push infection-causing bacteria up into the uterus, fallopian tubes, and ovaries. This can cause more serious problems.

What about pregnancy?

Some STDs can also be passed on to the baby during pregnancy, birth, or breastfeeding.

It is important for all pregnant women to be tested for STDs. Treatment of STDs can prevent the effects of the STD on the baby. If you are pregnant or breastfeeding and have an STD, you should talk to your health care provider about the risk of passing the STD to your baby.

Some STDs can cause:

• Early birth
• Low birth weights
• Other severe problems in the newborn baby

If you are pregnant, you can become infected with the same sexually transmitted diseases (STDs) as women who are not pregnant. Pregnant women should ask their doctors about getting tested for STDs, since some doctors do not routinely perform these tests. This fact sheet answers basic questions about STDs during pregnancy.

I’m pregnant. Can I get an STD?

Yes, you can. Women who are pregnant can become infected with the same STDs as women who are not pregnant. Pregnancy does not provide women or their babies any additional protection against STDs. Many STDs are ‘silent,’ or have no symptoms, so you may not know if you are infected. If you are pregnant, you should be tested for STDs, including HIV (the virus that causes AIDS), as a part of your medical care during pregnancy. The results of an STD can be more serious, even life-threatening, for you and your baby if you become infected while pregnant. It is important that you are aware of the harmful effects of STDs and how to protect yourself and your unborn baby against infection. If you are diagnosed with an STD while pregnant, your sex partner(s) should also be tested and treated.

How can STDs affect me and my unborn baby?

STDs can complicate your pregnancy and may have serious effects on both you and your developing baby. Some of these problems may be seen at birth; others may not be discovered until months or years later. In addition, it is well known that infection with an STD can make it easier for a person to get infected with HIV. Most of these problems can be prevented if you receive regular medical care during pregnancy. This includes tests for STDs starting early in pregnancy and repeated close to delivery, as needed.

Should I be tested for STDs during my pregnancy?

Yes. Testing and treating pregnant women for STDs is a vital way to prevent serious health complications to both mother and baby that may otherwise happen with infection. The sooner you begin receiving medical care during pregnancy, the better the health outcomes will be for you and your unborn baby. The Centers for Disease Control and Prevention’s 2015 STD Treatment Guidelines recommend screening pregnant women for STDs.

Be sure to ask your doctor about getting tested for STDs. It is also important that you have an open, honest conversation with your provider and discuss any symptoms you are experiencing and any high-risk sexual behavior that you engage in, since some doctors do not routinely perform these tests. Even if you have been tested in the past, you should be tested again when you become pregnant.

Can I get treated for an STD while I’m pregnant?

It depends. STDs, such as chlamydia, gonorrhea, syphilis, trichomoniasis and BV can all be treated and cured with antibiotics that are safe to take during pregnancy. STDs that are caused by viruses, like genital herpes, hepatitis B, or HIV cannot be cured. However, in some cases these infections can be treated with antiviral medications or other preventive measures to reduce the risk of passing the infection to your baby. If you are pregnant or considering pregnancy, you should be tested so you can take steps to protect yourself and your baby.

How can I reduce my risk of getting an STD while pregnant?

The only way to avoid STDs is to not have vaginal, anal, or oral sex.

If you are sexually active, you can do the following things to lower your chances of getting chlamydia:

• Being in a long-term mutually monogamous relationship with a partner who has been tested and has negative STD test results;
• Using latex condoms the right way every time you have sex.

Some infections—such as Zika, gonorrhea, chlamydia, HIV, and syphilis—can pass to the fetus during pregnancy or to the infant during delivery, causing short- and long-term health problems. However, the risk of transmission can be lowered or even eliminated with appropriate treatments.

For this reason, it is important for a pregnant woman to be tested for STDs/STIs as a part of her prenatal care. Prenatal STI testing can determine whether a pregnant woman has an infection that can be cured or controlled with drug treatment, which decreases the chances that the infant will contract the disease. The pregnant woman and her health care provider can take other steps to protect her health and her infant's health if the STI is one that cannot be cured or treated.

Some examples of ways to reduce or eliminate risk of transmission include the following:

• HIV can be passed from mother to infant during pregnancy before birth, at the time of delivery, or after birth during breastfeeding. Treatment during pregnancy near delivery prevents this transmission.
• Recent research also shows that, for HIV-infected mothers whose immune system is in good health, treatment during breastfeeding virtually eliminates transmission of HIV through breastmilk.Women who have HIV but whose immune systems are not in good health should not breastfeed their infants if safe alternatives, such as infant formula, are available.
• If a woman has active herpes lesions, untreated HIV, or an HIV viral load that is not suppressed, the infant can be delivered by cesarean section (also referred to as C section) to prevent transmission of the infection.
• For infections, such as gonorrhea, a pregnant woman and her sexual partner can be treated before the birth, and the infant can be treated at birth to prevent infection.
• In most hospitals, infants' eyes are routinely treated with an antibiotic ointment shortly after birth. The ointment can prevent blindness from exposure to gonorrhea or chlamydia bacteria during delivery, in case the pregnant woman had an undetected infection.
• Women who are pregnant or are thinking about getting pregnant are advised not to travel to areas where Zika infection has been reported. Preventing mosquito bites can also reduce the risk for infection and transmission.

STIs during pregnancy can also cause:

• Miscarriage (fetal loss before 20 weeks)
• Ectopic pregnancy (when the embryo implants outside of the uterus, usually in a fallopian tube)
• Preterm labor and delivery (before 37 completed weeks of pregnancy)
• Low birth weight
• Birth defects, including blindness, microcephaly, deafness, bone deformities, and intellectual disability
• Stillbirth (fetal loss at or after 20 weeks)
• Illness in the newborn period (first month of life)
• Newborn death
• Health complications in the mother

Bacterial vaginosis (BV), a common cause of vaginal discharge in women of childbearing age, is a polymicrobial clinical syndrome resulting from a change in the vaginal community of bacteria. Although BV is often not considered an STD, it has been linked to sexual activity. Women may have no symptoms or may complain of a foul-smelling, fishy, vaginal discharge.

BV during pregnancy has been associated with serious pregnancy complications, including premature rupture of the membranes surrounding the baby in the uterus, preterm labor, premature birth, chorioamnionitis, as well as endometritis. While there is no evidence to support screening for BV in pregnant women at high risk for preterm delivery, symptomatic women should be evaluated and treated. There are no known direct effects of BV on the newborn.

Chlamydia is the most common sexually-transmitted bacterium in the United States. Although the majority of chlamydial infections (including those in pregnant women) do not have symptoms, infected women may have abnormal vaginal discharge, bleeding after sex, or itching/burning with urination.

Untreated chlamydial infection has been linked to problems during pregnancy, including preterm labor, premature rupture of membranes, and low birth weight. The newborn may also become infected during delivery as the baby passes through the birth canal. Exposed newborns can develop eye and lung infections.

Gonorrhea is a common STD in the United States. Untreated gonococcal infection in pregnancy has been linked to miscarriages, premature birth and low birth weight, premature rupture of membranes, and chorioamnionitis. Gonorrhea can also infect an infant during delivery as the infant passes through the birth canal. If untreated, infants can develop eye infections. Because gonorrhea can cause problems in both the mother and her baby, it is important for providers to accurately identify the infection, treat it with effective antibiotics, and closely follow up to make sure that the infection has been cured.

Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). A mother can transmit the infection to her baby during pregnancy. While the risk of an infected mother passing HBV to her baby varies, depending on when she becomes infected, the greatest risk happens when mothers become infected close to the time of delivery. Infected newborns also have a high risk (up to 90%) of becoming chronic HBV carriers themselves. Infants who have a lifelong infection with HBV are at an increased risk for developing chronic liver disease or liver cancer later in life. Approximately 25% of infants who develop chronic HBV infection will eventually die from chronic liver disease. By screening your pregnant patients for the infection and providing treatment to at-risk infants shortly after birth, you can help prevent mother-to-child transmission of HBV.

Hepatitis C is a liver infection caused by the hepatitis C virus (HCV), and can be passed from an infected mother to her child during pregnancy. In general, an infected mother will transmit the infection to her baby 10% of the time, but the chances are higher in certain subgroups, such as women who are also infected with HIV. In some studies, infants born to HCV-infected women have been shown to have an increased risk for being small for gestational age, premature, and having a low birth weight. Newborn infants with HCV infection usually do not have symptoms, and a majority will clear the infection without any medical help.

Herpes Simplex Virus (HSV) has two distinct virus types that can infect the human genital tract, HSV-1 and HSV-2. Infections of the newborn can be of either type, but most are caused by HSV-2. Generally, the symptoms of genital herpes are similar in pregnant and in nonpregnant women; however, the major concern regarding HSV infection relates to complications linked to infection of the newborn. Although transmission may occur during pregnancy and after delivery, the risk of transmission to the neonate from an infected mother is high among women who acquire genital herpes near the time of delivery and low among women with recurrent herpes or who acquire the infection during the first half of pregnancy. HSV infection can have very serious effects on newborns, especially if the mother’s first outbreak occurred during the third trimester. Cesarean section is recommended for all women in labor with active genital herpes lesions or early symptoms, such as vulvar pain and itching.

Human immunodeficiency virus (HIV) is the virus that causes acquired immune deficiency syndrome (AIDS). HIV destroys specific blood cells that are crucial to helping the body fight diseases. According to CDC’s HIV surveillance report, women make up 19% of all new HIV diagnoses in the United States and dependent areas. The most common ways that HIV passes from mother to child are during pregnancy, childbirth, or breastfeeding. However, when HIV is diagnosed before or early during pregnancy and appropriate steps are taken, the risk of mother-to-child transmission can be less than 1%. A mother who knows early in her pregnancy that she has HIV has more time to consult with you—her healthcare provider—and decide on effective ways to protect her health and that of her unborn baby.

Human papillomaviruses (HPV) are viruses that most commonly involve the lower genital tract, including the cervix, vagina, and external genitalia. Genital warts frequently increase in number and size during pregnancy. Genital warts often appear as small cauliflower-like clusters which may burn or itch. If a woman has genital warts during pregnancy, you may elect to delay treatment until after delivery. When large or spread out, genital warts can complicate a vaginal delivery. In cases where there are large genital warts that are blocking the birth canal, a cesarean section may be recommended. Infection of the mother may be linked to the development of laryngeal papillomatosis in the newborn—a rare, noncancerous growth in the larynx.

Syphilis is primarily a sexually-transmitted disease, but it may be transmitted to a baby by an infected mother during pregnancy. Transmission of syphilis to a developing baby can lead to a serious multisystem infection, known as congenital syphilis. Recently, there has been a sharp increase in the number of congenital syphilis cases in the United States. Syphilis has been linked to premature births, stillbirths, and, in some cases, death shortly after birth. Untreated infants that survive tend to develop problems in multiple organs, including the brain, eyes, ears, heart, skin, teeth, and bones.

Vaginal infection due to the sexually-transmitted parasite Trichomonas vaginalis is very common. Although most people report no symptoms, others complain of itching, irritation, unusual odor, discharge, and pain during urination or sex. If you have a pregnant patient with symptoms of trichomoniasis, she should be evaluated for Trichomonas vaginalis and treated appropriately. Infection in pregnancy has been linked to premature rupture of membranes, preterm birth, and low birth weight infants. Rarely, the female newborn can acquire the infection when passing through the birth canal during delivery and have vaginal discharge after birth.

Screening and prompt treatment are recommended at least annually for all HIV-infected women, based on the high prevalence of T. vaginalis infection, the increased risk of pelvic inflammatory disease (PID) associated with this infection, and the ability of treatment to reduce genital tract viral load and vaginal HIV shedding. This includes HIV-infected women who are pregnant, as T. vaginalis infection is a risk factor for vertical transmission of HIV. For other pregnant women, screening may be considered at the discretion of the treating clinician, as the benefit of routine screening for pregnant women has not been established. Screening might be considered for persons receiving care in high-prevalence settings (e.g., STD clinics or correctional facilities) and for asymptomatic persons at high risk for infection. Decisions about screening might be informed by local epidemiology of T. vaginalis infection. However, data are lacking on whether screening and treatment for asymptomatic trichomoniasis in high prevalence settings or persons at high risk can reduce any adverse health events and health disparities or reduce community burden of infection.

STDs can complicate pregnancy and may have serious consequences for both a woman and her developing baby.

A critical component of appropriate prenatal care is ensuring that pregnant patients are tested for STDs. Test your pregnant patients for STDs starting early in their pregnancy and repeat close to delivery, as needed. To ensure that the correct tests are being performed, we encourage you to have open, honest conversations with your pregnant patients and, when possible, their sex partners about symptoms they have experienced or are currently experiencing and any high-risk sexual behaviors in which they engage. The table below includes CDC’s screening recommendations for pregnant women.

As a provider working with pregnant patients, it is important for you to know the ways in which each STD can impact a woman and her developing baby.

STDs, such as chlamydia, gonorrhea, syphilis, and trichomoniasis can all be treated and cured with antibiotics that are safe to take during pregnancy. Viral STDs, including genital herpes, hepatitis B, and HIV cannot be cured. However, in some cases these infections can be treated with antiviral medications or other preventive measures to reduce the risk of passing the infection to the baby.

After obtaining a sexual history from your patient, you should encourage risk reduction by providing prevention counseling. The most reliable way to avoid transmission of STDs is to abstain from oral, vaginal, and anal sex or to be in a long-term, mutually monogamous relationship with a partner known to be uninfected. For patients who are being treated for an STD other than HIV (or whose partners are undergoing treatment), counseling that encourages abstinence from sexual intercourse until completion of the entire course of medication is crucial. Latex male condoms, when used consistently and correctly, can reduce the risk of transmitting or acquiring STDs and HIV.