What causes it: Doctors aren't sure, but risk factors include carrying multiple fetuses, a history of premature labor, an abnormality of the cervix, and certain vaginal infections.
Symptoms: See your physician right away if you notice bloody or watery vaginal discharge or experience abdominal cramps or backache.
Treatment: Bed rest can sometimes reduce pressure on the cervix, making it less likely to dilate. But a new study indicates that bed rest may do more harm than good in some situations, so ask your doctor whether it's necessary. "We also encourage drinking lots of fluids, because dehydration can cause uterine contractions," says Iffath Hoskins, M.D., executive director of the Women's Services Memorial Health Medical Center, in Savannah.
Can you prevent preterm labor? Reduce your risk by having your thyroid checked before getting pregnant. Women who have untreated thyroid disease are more likely to deliver prematurely. Before you conceive, it's also important to get screened for bacterial vaginosis, which has been linked to premature birth. Stress-management techniques such as yoga can also help, because several studies have found a link between high levels of stress hormones and preterm delivery rates. Finally, if you have a history of preterm delivery, ask your doctor about progesterone shots, which may reduce the risk of premature birth by almost 20 percent.
What causes it: One study suggests preeclampsia may be caused by a protein that halts the growth of blood vessels in the placenta, while another study suggests the odds for it increase with a woman's prepregnancy body-mass index. At highest risk: moms carrying more than one fetus, women over 40, or those who have a close relative who's had preeclampsia.
Symptoms: High blood pressure, swelling in the hands and feet, severe headaches, blood in the urine, or extreme nausea.
Treatment: If symptoms are mild, most physicians suggest bed rest. Vitamins E and C may also help. Delivery usually ends the condition.
Can you prevent preeclampsia? You can decrease the likelihood by staying at a healthy weight, eating a nutritious diet, and getting regular exercise.
What causes it: Your pancreas is unable to produce enough insulin to counteract pregnancy hormones that increase blood-sugar levels.
Symptoms: May include thirst, increased urination, and blurred vision. But women often have no symptoms at all.
Treatment: Most cases can be controlled with a high-fiber diet that's low in sugars, though some women need insulin injections or the drug glyburide. Gestational diabetes usually disappears after delivery, but about half of women with gestational diabetes develop type 2 diabetes later in life.
Can you prevent gestational diabetes? You can reduce your risk by staying at a healthy weight, eating a low-fat, high-fiber diet, and exercising regularly.
What causes it: Doctors aren't sure, but risks include carrying multiple fetuses, having had C-sections or abortions, and being over 40.
Symptoms: Bleeding during the second or third trimester.
Treatment: If bleeding is light, your doctor may just monitor you closely. In 90 percent of cases, the placenta moves away from the cervix on its own. If the placenta completely blocks your cervix, however, your doctor may recommend bed rest. Recurrent bouts of bleeding may require hospitalization.
Can you prevent placenta previa? No. Simply report any bleeding to your doctor immediately.
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