There are many types of infections that can cause an increased risk of miscarriage, stillbirth, or neonatal death. Not every woman who gets ones of these infections will have a pregnancy loss. It is also worth noting that these infections are not the most common cause of pregnancy loss -- chromosomal abnormalities are the number one cause. This list does not cover every possible infection that can occur during pregnancy, but it touches on some of the most common, and the ones women often have concerns about.
Sexually Transmitted Infections
Bacterial vaginosis (BV) is an excess growth of normal vaginal bacteria. BV is not a sexually transmitted disease, but as a vaginal infection, many women notice the characteristic “fishy” odor of BV after intercourse. However, sometimes there is no noticeable odor, and often does not require treatment in non-pregnant women. In pregnancy, however, BV has been associated with an increased risk in second trimester miscarriage. Later in pregnancy, BV may cause uncomfortable uterine contractions. It is easily treated with an antibiotic and has no lasting health effects.
Chlamydia is a sexual transmitted infection, and can lead to pelvic inflammatory disease (PID). PID is a known cause of ectopic pregnancy and infertility. Ectopic pregnancy is an obstetric emergency and requires surgery to prevent serious complications for the mother, including risk of death. Some studies suggest chlamydia also may contribute to miscarriage in the first trimester. Like all bacterial infections, chlamydia is treated with antibiotics. Condoms can protect you against contracting chlamydia.
Although there is no conclusive evidence that gonorrhea causes pregnancy loss, several studies have linked the sexually transmitted infection with miscarriage, preterm labor, and ectopic pregnancy (if it goes untreated long enough to cause PID). Gonorrhea infection during birth can cause life-threatening health problems for a baby. You can protect yourself against gonorrhea by using condoms during intercourse. If you already have it, gonorrhea can be treated with antibiotics.
In the past, HIV infection was thought to dramatically increase risk of miscarriage. Since routine testing of pregnant women, and more effective drug treatment, however, HIV+ women are usually capable of having a healthy, full-term baby. There is no cure for HIV, but there are excellent treatments available to control the virus. The spread of HIV can be prevented through condom use and other safe sex techniques.
Herpes, another sexually transmitted infection, is a common viral infection that can cause painful sores on the genitals or mouth. Some research has found a link between recurrent miscarriage and undiagnosed herpes infection, but so far no cause has been established. There does not appear to be any increased risk of pregnancy loss with HSV. There is a risk of the fetus contracting HSV during birth, however, so medication may be given in the weeks leading up to birth. If a woman has active herpes lesions at the time of labor, physicians recommend a c-section for delivery.
Syphilis is a sexually transmitted infection that can be easily treated with antibiotics. Because it is one of the most dangerous STDs to have during pregnancy, women are routinely screened for it during prenatal care. Untreated, syphilis can lead to stillbirth of neonatal death for up to 40% of infected women. There is also a risk of the baby developing congenital syphilis, which can cause long-term life-threatening or disabling complications.Food-Borne Illnesses
Although E. coli lives in everyone’s intestinal tracts, some forms of it have been associated with a risk of miscarriage. There is no specific food source associated with E. coli. It can be found in any unsanitary or undercooked food, contaminated water, or unwashed hands. There is a risk of miscarriage associated with E. coli infection. The best way to avoid E. coli is to follow proper food-handling techniques, and to wash your hands frequently, especially before eating or touching your mouth.
Listeria is a bacteria found in certain kinds of foods. It is most commonly associated with unpasteurized cheeses, although it can be found in fresh produce (recently, an outbreak of listeriosis was traced back to cantaloupe). Listeriosis (infection due to listeria exposure) has a known risk for miscarriage. It is avoidable through proper food handling, and good hand-washing.
Salmonella is a bacteria which can cause infections in humans. It is commonly found in raw or undercooked animal sources, like chicken, eggs, and unpasteurized dairy products. It may also be carried by reptiles, including household pets like turtles, snakes, and lizard. Salmonella has been associated with an increased risk of miscarriage. Infection can be avoided through good food-handling techniques, and thorough hand-washing.
Toxoplasmosis is one of the infections with a known risk of miscarriage. It is commonly associated with being exposed to cat feces, which is why pregnant women used to be advised to avoid cats. Many obstetricians still recommend that women avoid cleaning litterboxes during pregnancy. Toxoplasmosis also can be contracted by eating undercooked meat, but good food-handling techniques can all but eliminate the risk of contracting a food-borne illness.