Sexually Transmitted Diseases (STDs) and Pregnancy Problems

Having a sexually transmitted disease (STD) or sexually transmitted infection (STI, as they're more often referred to in the medical community), during pregnancy can bring an increased risk of miscarriage, stillbirth, preterm delivery,​ and other maternal and fetal complications.

It's also possible for an infection to pass to a baby in the womb or during labor and even during breastfeeding. The exact risk varies by the type of STI, adequate treatment availability, and how well controlled the condition is during the pregnancy, along with other factors.

However, sexually transmitted infections can be managed to reduce or eliminate these risks. If you have an STI, or if you're worried that you might, talk to a healthcare provider about treatment and prenatal care. Some infections are looked for as part of routine prenatal screening, especially in high-risk populations (for example, trichomonas), but many are not.

Pregnant young woman having a consultation with her doctor
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Syphilis

All women should be tested for syphilis during pregnancy because it can be fatal for a baby, and it can also be transmitted from mother to child. Because there are several stages of the disease, some people with syphilis may not know that they are infected. Pregnant women with syphilis can be treated with penicillin to prevent mother-to-child transmission during labor and delivery.

Human Immunodeficiency Virus (HIV)

Human immunodeficiency virus (HIV) infection in pregnancy can lead to miscarriage and stillbirth. It can also be passed from mother to baby. But today's highly effective drugs can prevent mother-to-child transmission of HIV and improve pregnancy outcomes. The use of antiretroviral therapy (ART) can now prevent transmission around 98% of the time.

As with syphilis, the Centers for Disease Control and Prevention (CDC) recommends that all women be tested for HIV in early pregnancy, regardless of whether they have risk factors.

Viral Hepatitis

The risk of viral hepatitis during pregnancy varies by the type of hepatitis. The viral strains common in the U.S. do not increase the risk of miscarriage, but babies can become infected in the womb or during labor.

Hepatitis B and (much less commonly) hepatitis C can be passed from mother to baby during pregnancy. Because hepatitis B can be dangerous for babies, all newborns should be vaccinated against hepatitis B, regardless of whether or not their mother has a known infection.

Babies born to mothers with hepatitis B must get the vaccine within 12 hours of birth. They also receive an immune globulin treatment to prevent a chronic hepatitis infection.​ Chronic hepatitis B infection does not often cause symptoms in newborns, but long-term chronic infections are a significant cause of serious complications like cirrhosis and liver cancer.

Herpes

Genital herpes may carry a risk of miscarriage, but research is inconclusive. While some studies have shown a greater risk, others have not, and herpes is a very common infection. Currently, the CDC does not recommend screening pregnant women for herpes infection.

Babies can acquire herpes if a mother contracts the infection during pregnancy or if active lesions are present at birth and the baby is delivered vaginally. Therefore, mothers with active lesions often need to deliver by cesarean section. Mothers can also be prescribed an antiviral medication during the last month of pregnancy to prevent an outbreak and allow for a vaginal delivery.

Bacterial Vaginosis (BV)

Bacterial vaginosis (BV) is an infection of the vagina caused by an overgrowth of certain types of bacteria. It is not actually a sexually transmitted infection but it can be associated with sexual activity, especially if one has multiple partners. Bacterial vaginosis increases the risk of pregnancy problems including premature birth.

Screening for BV is not routine during pregnancy, so tell your healthcare provider if you experience symptoms including a gray vaginal discharge with an unpleasant fishy odor and itching or burning. This infection is easily treated in pregnancy with antibiotics.

Gonorrhea

If untreated, gonorrhea can increase the risk of pelvic inflammatory disease (PID), which can lead to damage to the fallopian tubes, ectopic pregnancy, and fertility problems. Gonorrhea can also increase the risk of:

Gonorrhea may also be transmitted to the baby during birth. If untreated, it can result in infections of the eye, joints, and blood.

Asymptomatic infections are common, so doctors may screen for gonorrhea at an early prenatal appointment. Antibiotics can resolve the infection if it is present. It is also important to treat sex partners so that pregnant women do not get reinfected and to retest after treatment to ensure that the infection has been cured.

Chlamydia

Chlamydia is the most common sexually transmitted bacteria in the U.S., and like gonorrhea, it's often present without symptoms. Still, it is not usually included in routine prenatal screening unless you have a risk factor (being under age 25 is a risk factor).

Chlamydia is associated with pregnancy complications including preterm labor, premature rupture of membranes, and low birth weight. Babies can also be exposed to the bacteria during delivery and develop eye and lung infections. Chlamydia can be treated with antibiotics. As with gonorrhea, it is important to retest after treatment to make sure the infection is no longer present.

A Word From Verywell

While having an infection of any kind during pregnancy can be scary, treatments are available for STIs, as well as other bacterial and viral infections. Check with your doctor or midwife anytime you have questions about your health or are experiencing symptoms that concern you.

9 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Krissi Danielsson
Krissi Danielsson, MD is a doctor of family medicine and an advocate for those who have experienced miscarriage.