Hypertension, or blood pressure that is higher than normal, is a common pregnancy complication. There are several types of hypertension in pregnancy. Hypertension can be chronic--occurring before pregnancy or early in pregnancy. Pregnancy-induced hypertension (PIH), which occurs after 20 weeks of pregnancy, is most likely caused by immune factors. Fifteen to twenty five percent of women with chronic hypertension also develop PIH. Both types of hypertension can pose serious risks to mother and baby.
Effects of Medications on the Fetus
Many medications taken for hypertension are implicated in increasing the risk of birth defects. Different types of anti-hypertensive medications have different effects. The U.S. Department of Health and Human Services reports that beta blockers are associated with intrauterine growth retardation (IUGR), or babies that are smaller than normal. Anti-hypertensives categorized as angiotensin-converting enzyme, or ACE, inhibitors are associated with kidney problems if taken in the second half of pregnancy. ACE inhibitors may also cause IUGR, underdeveloped lungs and underdevelopment of the fetal skull. Women with chronic hypertension hoping to become pregnant should discuss medications choices with their doctor.
Eclampsia
Eclampsia is a serious complication of preeclampsia, also called pregnancy induced hypertension (PIH). Eclampsia occurs in every 1 in 2,000 to 3,000 pregnancies, according to the Milton S. Hershey Medical Center. Brain swelling in eclampsia causes seizures; maternal and/or fetal death may occur. The treatment for eclampsia is delivery, even if the baby will be very premature.
Placental Problems
Hypertension can reduce blood flow to the placenta. Placental abruption, wherein the placenta separates from the uterine wall, can occur as a complication of chronic hypertension or PIH. In 50 to 80 percent of cases of abruption in severe PIH, fetal death results from abruption, Healthline.com reports. Maternal hemorrhage may also occur. Decreased blood flow through the placenta can lead to fetal intrauterine growth retardation.
HELLP Syndrome
HELLP is a life-threatening complication that occurs in 2 to 12 percent of cases of pregnancy-induced hypertension, the University of Virginia states. HELLP stands for hemolysis, elevated liver enzymes and low platelets. HELLP causes anemia, blood-clotting problems, fluid in the lungs and placental abruption. Symptoms of HELLP include abdominal pain, headache, edema, high blood pressure and protein in the urine. A blood-clotting disorder called disseminated intravascular coagulation (DIC) can cause severe hemorrhage.
