Cause: Unknown, although a recent study found a higher risk when either the mom or dad has a family history of preeclampsia, suggesting a genetic link. Preeclampsia affects about 5 to 8 percent of pregnant women—often in the third trimester, though sometimes earlier—and is more common in first pregnancies and in women who have gestational diabetes, are over 40 or under 18, overweight, sedentary or carrying multiples.
Danger: The mother may develop any of the following: high blood pressure; protein in the urine; swelling of the hands and feet; sudden weight gain of as much as a pound or more a day; blurred vision; severe headaches; dizziness and intense stomach pain. Preeclampsia can slow fetal growth and boost the risk of the placenta separating from the uterine wall. In very rare cases, it develops into eclampsia, which can cause stroke, liver damage, coma and death of mother and baby.
Treatment: "The only true treatment is to deliver the baby," Evans says. Bed rest and, in some cases, blood pressure medi-cation can prevent mild preeclampsia from getting worse. Mind-body exercises, such as relaxation breathing, meditation and imagery, have been shown to lower blood pressure, which can be helpful in the management of preeclampsia.
Cause: Too much (hyper) or too little (hypo) thyroid hormone, resulting in an over- or underactive metabolism. Thyroid disease occurs in about 3 percent of pregnancies, and hypothyroidism is five times more common than hyperthyroidism. "Most of the time, thyroid disease precedes the pregnancy," says Ashi Daftary, M.D., a maternal-fetal medicine specialist at Magee-Women's Hospital of the University of Pittsburgh Medical Center. Many women aren't aware they have it, however. The increased medical scrutiny received during pregnancy often reveals the condition, and many experts maintain that all expectant women should be tested for it.
Danger: If not controlled, thyroid disease can increase the risk for miscarriage, fetal growth delays, preterm birth, preeclampsia, impaired neurological development and, in rare cases, death of the fetus.
Treatment: For hyperthyroidism, a doctor may prescribe oral medications that suppress thyroid hormone production. For hypothyroidism, thyroid-replacement pills are generally taken.
Cause: "Hormonal changes affect blood supply to the gums," says Sally J. Cram, D.D.S., a periodontist (gum specialist) in Washington, D.C., and consumer advisor for the American Dental Association. "Pregnant women may experience red, puffy or irritated and tender gums that bleed easily, particu-larly during the second and early third trimester." An estimated 60 to 75 percent of women get this "pregnancy gingivitis," an aggravated response to the bacterial film, or plaque, that builds up on teeth. If neglected, it can lead to periodontal disease, an infection of the gums and bone under the teeth.
Danger: Women with untreated perio-dontal disease are seven times more likely to deliver a preterm or low-birth-weight baby. The disease also can cause large, noncancerous "pregnancy tumors" on the gums that may require surgical removal after delivery.
Treatment: Brush twice and floss once daily. If you need help controlling plaque, your dentist may recommend an antibacterial mouth rinse and professional teeth cleaning every two to three months during pregnancy.