Pregnancy and High Blood Pressure (Chronic hypertension & gestational hypertension)

Pregnancy and High Blood Pressure

Hypertension, or high blood pressure, can cause serious complications for a fetus and the mother. Some pregnant women have chronic hypertension, meaning they had the condition before they became pregnant. Others develop gestational hypertension during pregnancy.

Hypertensive disorders are the number two cause of maternal deaths in the United States. That’s why it’s important to pay attention to your blood pressure before it turns into the serious condition called preeclampsia.

What is chronic hypertension?

Women who have hypertension before pregnancy will continue to have this condition during pregnancy. When a woman has pre-existing hypertension or develops hypertension before the 20th week of pregnancy, this is called chronic hypertension.

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In fact, nearly one in four women with chronic hypertension will develop preeclampsia during pregnancy, usually at mid-term. In such cases, the outlook for both mother and child is worse than it is for women who develop high blood pressure during their pregnancy. Pregnant women with chronic hypertension are at higher risk for premature birth, restricted growth or death of the fetus, congestive heart failure and renal failure.

How does pregnancy affect chronic hypertension?

Most risks are not increased for most women with mild chronic hypertension if there are no other complications. However, if hypertension is severe, if there are other conditions such as diabetes, or if preeclampsia develops along with chronic hypertension, risks are much greater for mother and baby.

Risks of severe chronic hypertension in pregnancy may include, but are not limited to, the following:

Risks to the fetus and newborn depend on the severity of the disease and may include, but are not limited to, the following:

Management of chronic hypertension during pregnancy

Prenatal care and careful monitoring of blood pressure and other factors are important. Women with high blood pressure often need to continue taking their antihypertensive medication. Your doctor may switch you to a safer antihypertensive medication during pregnancy.

In 2006, an article in the New England Journal of Medicine discussed the relationship between ACE inhibitors, medications used to control blood pressure, and the occurrence of congenital birth defects. Researchers determined that women taking ACE inhibitors were about three times as likely to deliver a baby with congenital defects as women who were taking some other type of medication for high blood pressure.

Because of this, ACE inhibitors are not recommended in the second and third trimesters. Talk with your doctor if you are currently taking an ACE inhibitor for hypertension.

If pregnancy causes your blood pressure to rise, there are some steps you can take to keep it under control:

Laboratory tests may be performed on a regular basis to check the levels of various blood and urine substances related to hypertension. Other tests to monitor heart and kidney function may also be performed. Fetal testing may begin in the second trimester and may include:

What is gestational hypertension?

Gestational hypertension is a hypertensive disorder that develops about halfway through pregnancy. It occurs in about 5 to 8 percent of all pregnancies and usually goes away after pregnancy. If it does not, the diagnosis is changed to chronic hypertension.

Gestational hypertension can develop into preeclampsia. This condition occurs most often in young women with a first pregnancy. It is more common in twin pregnancies, in women over the age of 35, in women with chronic hypertension or who had hypertension in a previous pregnancy, in African-American women, and in women with diabetes.

Gestational hypertension is diagnosed when blood pressure readings are higher than 140/90 mm Hg after 20 weeks of pregnancy with normal blood pressure.

Preeclampsia (also known as toxemia) is diagnosed when a woman with gestational hypertension also has increased protein in her urine.

Eclampsia is a severe form of preeclampsia. Women with eclampsia have seizures resulting from the condition. Eclampsia occurs in about one in 1,600 pregnancies and develops near the end of pregnancy, in most cases.

HELLP syndrome is a complication of severe preeclampsia or eclampsia. HELLP syndrome is a group of physical changes including the breakdown of red blood cells, changes in the liver, and low platelets (cells found in the blood that are needed to help the blood to clot in order to control bleeding).

What causes gestational hypertension?

The cause of gestational hypertension is unknown. Some conditions may increase the risk of developing the condition, including the following:

Why is gestational hypertension a concern?

With high blood pressure, there is an increase in the resistance of blood vessels. This may hinder blood flow in many different organ systems in the expectant mother including the liver, kidneys, brain, uterus, and placenta.

There are other problems that may develop as a result of gestational hypertension. Placental abruption (premature detachment of the placenta from the uterus) may occur in some pregnancies. Gestational hypertension can also lead to fetal problems including intrauterine growth restriction (poor fetal growth) and stillbirth.

If untreated, severe gestational hypertension may cause dangerous seizures and even death in the mother and fetus. Because of these risks, it may be necessary for the baby to be delivered early, before 37 weeks gestation.

What are the symptoms of gestational hypertension?

The following are the most common symptoms of high blood pressure in pregnancy. However, each woman may experience symptoms differently. Symptoms may include:

How is gestational hypertension diagnosed?

Diagnosis is often based on the increase in blood pressure levels, but other symptoms may help establish gestational hypertension as the diagnosis. Tests for gestational hypertension may include the following:

Treatment for gestational hypertension

Specific treatment for gestational hypertension will be determined by your doctor based on:

The goal of treatment is to prevent the condition from becoming worse and to prevent it from causing other complications. Treatment for gestational hypertension may include:

Prevention of gestational hypertension

Early identification of women at risk for gestational hypertension may help prevent some complications of the disease. Education about the warning symptoms is also important because early recognition may help women receive treatment and prevent worsening of the disease.

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