What should I know about pregnancy and high blood pressure?
About 5% to 10% of pregnancies experience complications due to high blood pressure.13 High blood pressure during pregnancy is the second largest cause of maternal death, responsible for 15% of all that occur during pregnancy.14
There are two ways high blood pressure can affect pregnancy. The first is when you have high blood pressure and later become pregnant. This is referred to as chronic hypertension during pregnancy. Most women with chronic hypertension during pregnancy are at low risk for heart disease during pregnancy. However, in some cases it can cause serious problems, such as preeclampsia, that can threaten the lives of both the mother and the fetus. Certain types of blood pressure medicines can cause birth defects, so be sure to talk to your doctor if you have high blood pressure and plan to become pregnant so your medication can be adjusted if necessary.
There are also high blood pressure disorders that occur in women who may not have had high blood pressure before they became pregnant. These are preeclampsia- eclampsia and gestational hypertension.
What is preeclampsia?
Preeclampsia (“ toxemia of pregnancy”) is diagnosed if the mother has high blood pressure and protein in the urine. The protein is a sign of kidney problems. Preeclampsia usually occurs after the 20th week of pregnancy and can result in seizures (called eclampsia). It is a very serious condition that occurs in about 5% of pregnancies, and risks include death for the mother and premature birth, stillbirth, and low birth weight for the baby. Risk factors for preeclampsia include older age, high blood pressure, first pregnancies, and multiple births. There is no way to prevent preeclampsia and it can only be cured by delivering the baby. During pregnancy, it can be managed with medications to lower blood pressure and prevent convulsions. The problems associated with preeclampsia, including high blood pressure, usually go away within 6 weeks of delivery.
Gestational hypertension is high blood pressure (greater than 140/90) that is diagnosed for the first time after midpregnancy. Usually, this condition is not dangerous and blood pressure returns to normal within 3 months after delivery. If blood pressure remains high more than 3 months after delivery, it is diagnosed as chronic high blood pressure.
Preeclampsia-eclampsia and gestational hypertension are not associated with an increased risk of heart disease or stroke. However, women who have gestational hypertension have an increased risk of developing high blood pressure later in life.
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