Sexually transmitted diseases can be dangerous in pregnancy.


Better to Know

If you're like most moms-to-be, thoughts of past partners and the possibility of sexually transmitted diseases (STDs) probably haven't crossed your mind -- but they should. Each year at least one in four Americans develops an STD and pregnant women are no exception. Since these conditions can pose special risks to you and your unborn baby, it's important to find out if you have an STD.

During an early prenatal visit, your healthcare provider may ask if you've ever been diagnosed with a sexually transmitted disease and offer to test you for a variety of conditions. To ensure a healthy pregnancy, it's wise to be tested. Since many STDs are symptomless, most women are not aware they have a problem. And while some sexually transmitted diseases can be easily cured with medication, others may not. Fortunately, if you have a problem, there are steps you can take to protect your unborn baby. Here are some common STDs and their treatment options.

Genital Herpes

About 25 percent of American women have genital herpes, which is caused by a group of viruses called herpes simplex. Since many infected moms-to-be don't experience symptoms, they can unknowingly pass the virus on to others, including their own babies.

Women who contract genital herpes for the first time may develop fever, fatigue, swollen glands, and body aches. A small percentage may also experience itchy, painful blisters in their genital area. Doctors diagnose herpes by looking at the sores, and in some cases, may take a swab of the blisters or do a blood test. The herpes virus remains in the body forever, causing some infected individuals to experience sporadic outbreaks throughout their lifetime.

The good news is that most moms-to-be with herpes don't pass it on to their children during vaginal delivery. The risk is highest (30 to 50 percent) when a pregnant woman contracts herpes (whether or not she has symptoms) for the first time late in pregnancy. Infected infants can develop skin or mouth sores and eye infections. Often, these problems can be treated safely with antiviral drugs, but there are occasions when the infection can spread to the baby's brain and internal organs. Unfortunately, despite treatment, as many as half of all babies with widespread infections die, with survivors often suffering from brain damage.

You can protect yourself and your unborn child from these risks by making sure you don't contract herpes for the first time during pregnancy. If there's a possibility you may have this condition, speak with your doctor to arrange a blood test. Testing is especially important if you or your partner has a history of herpes. If your partner has the virus, avoid intercourse when he has symptoms and use a condom even when he doesn't. Your doctor may even suggest avoiding intercourse altogether during the last trimester. It is also important to avoid oral sex if your partner has cold sores in his mouth, which are also caused by one of the herpes viruses.

If you do contract this disease for the first time during pregnancy, your doctor may prescribe acyclovir, an antiviral drug, which can shorten attacks and ease symptoms. Acyclovir may also reduce the risk of cesarean delivery for women who have frequent flare-ups of old herpes infections. If you experience a flare-up near delivery, the risk of passing the infection to your baby is low (less than 1 percent). However, if you continue to experience symptoms near your due date, your healthcare provider may recommend a cesarean delivery, which can protect your baby from infection.


About 10 percent of pregnant women have chlamydia. While most of them don't experience symptoms, a small number of women can develop vaginal discharge and a burning sensation during urination. If left untreated, chlamydia can spread to your upper genital tract, resulting in pelvic inflammatory disease, infertility, or an ectopic pregnancy (when the embryo becomes implanted outside the uterus, usually in a fallopian tube).

A study from the National Institute of Child Health and Human Development suggests that pregnant women with chlamydia have an increased risk of delivering prematurely. Those who don't seek treatment for this STD can also face an increased risk of miscarriage and premature rupture of the membranes (bag of waters).

Babies of untreated women usually become infected during vaginal delivery. These children frequently develop eye infections and pneumonia and must be treated with antibiotics.

The Centers for Disease Control and Prevention (CDC)recommends that all pregnant women be tested for chlamydia. Your healthcare provider can easily test you for this condition by taking a urine or vaginal fluid sample. Your partner should also be tested for this disease to prevent the possibility of transmitting the virus back and forth during pregnancy. Fortunately, this sexually transmitted disease can be cured with the use of antibiotics, preventing complications for you and your baby.

Bacterial Vaginosis and Trichomoniasis

About 16 percent of pregnant women develop bacterial vaginosis (BV), an infection caused by an overgrowth of bacteria that occurs naturally in the vagina. Some women with BV have vaginal discharge that has an unpleasant odor, burning on urination, and genital itching, while others don't experience any symptoms. Though doctors don't know for certain how a woman gets bacterial vaginosis, it appears more common in women who douche or in those who have new or multiple sex partners.

Some studies suggest that BV can double a woman's risk of preterm delivery. Your doctor may recommend antibiotics to reduce this risk if you develop symptoms. Since this condition is often symptomless, doctors sometimes test women who have a high risk of preterm labor (such as women who delivered prematurely in a previous pregnancy). Research also suggests that treating high-risk women with bacterial vaginosis (even if they have no symptoms) may reduce their risk of preterm birth.


Each year 2 million women contract trichomoniasis. This parasitic infection often causes yellowish-green, foul-smelling vaginal discharge, genital itching and redness, and sometimes, pain during sex and urination.

If left untreated, trichomoniasis may increase the risk of premature rupture of the membranes and preterm delivery. Infants rarely contract the infection during delivery but may develop a fever after birth.

Doctors often detect trichomoniasis by testing vaginal fluid. As with all STDs, both partners should be tested. Infections can be cured with metronidazole, a drug considered safe in pregnancy.

Genital Warts

One percent of sexually active adults contract genital warts. Appearing as small, cauliflower-shaped clusters, warts commonly appear as pink, white, or gray swellings in the genital area. The warts, which are caused by a large group of viruses called human papilloma, can itch or burn, though many women don't have symptoms. Some of these viruses can also increase the risk of cervical cancer.

Unfortunately, pregnancy-related hormones can cause genital warts to grow. Occasionally, these growths can become large enough to block the birth canal, making a cesarean delivery necessary. However, infected mothers rarely pass the virus on to their babies, so cesarean deliveries are not routinely recommended. If you have large, uncomfortable growths, removal with laser surgery or cryotherapy (freezing) is a safe option, but chemical treatments should be avoided. After pregnancy, genital warts often return to their prepregnancy size or may go away without treatment.

AIDS Awareness

AIDS (acquired immune deficiency syndrome) is one of the most frightening STDs today. Many women in the United States are living with HIV (the human immunodeficiency virus that causes AIDS), and many do not know it.

While unprotected sex is still the most common method of contracting the virus, intravenous drug use has become another frequent source of infection. Pregnant women who have the virus can pass it on to their babies during pregnancy, delivery, or breastfeeding.

The Centers for Disease Control and Prevention (CDC) and the March of Dimes both recommend that all pregnant women be offered counseling and voluntary testing for HIV. Moms-to-be who have the virus can now get treatment to protect their unborn babies. New drug treatments have been shown to reduce the risk of a treated mother's passing HIV on to her baby to 2 percent or less, compared with 15 to 25 percent of untreated mothers. Women who have high levels of the virus in their blood may also need cesarean delivery.

You can protect your baby from sexually transmitted diseases by making sure you don't get one during pregnancy or, if you do, by following through with all recommended treatment. It's also important to tell your doctor if you have been diagnosed with an STD in the past so that she can take the steps necessary to prevent future problems. By working with your doctor, you can help ensure that STDs won't harm your unborn baby.

Richard H. Schwarz, MD, obstetrical consultant to the March of Dimes, is past president of the American College of Obstetricians and Gynecologists; Vice Chairman for Clinical Services, Maimonides Medical Center; and Professor of Obstetrics and Gynecology, SUNY Downstate Medical Center, both in Brooklyn.

All content here, including advice from doctors and other health professionals, should be considered as opinion only. Always seek the direct advice of your own doctor in connection with any questions or issues you may have regarding your won health or the health of others.

American Baby