How Does High Blood Pressure Affect Pregnancy?

Having high blood pressure while pregnant can put stress on organs like your kidneys and heart. It also can increase your risk of developing heart disease.

Your heartbeat creates a force called blood pressure that pushes your blood against the walls of your arteries while carrying oxygen to different parts of your body. High blood pressure (or hypertension) is a condition where too much force is generated against the blood vessels in your body. 

During pregnancy, high blood pressure is a common occurrence among expectant mothers. 1 out of every 12 to 17 women between age 20 and 44 experience high blood pressure during pregnancy. 

Having high blood pressure while pregnant can put stress on organs like your kidneys and heart. It also can increase your risk of developing heart disease. 

High blood pressure during pregnancy can also lead to a situation where your doctor must induce labor early. If this happens, your baby could be born prematurely.  

High blood pressure during pregnancy can also lead to other complications, including:

• Restricted growth of your fetus caused by a decreased flow of nutrients
• The placenta detaching from the wall of your uterus
• A higher chance of having a cesarean birth (also called a C-section)

There are several different high blood pressure types that women experience while pregnant, including:

Chronic hypertension 

Women with chronic hypertension experienced high blood pressure before becoming pregnant or developed it before the 20th week of their pregnancy. Chronic hypertension can lead to the development of preeclampsia in your second or third trimester.

Gestational hypertension 

Gestational hypertension occurs only while a woman is pregnant. Doctors typically diagnose the condition after the 20th week of pregnancy or when the mother is close to delivering her baby. This form of high blood pressure during pregnancy usually goes away after the birth of your baby. 

Preeclampsia

Like gestational hypertension, preeclampsia develops after the 20th week of pregnancy. Preeclampsia differs from gestational hypertension in that it comes on quickly. Pregnant women with this form of high blood pressure have detectable protein in their urine and often end up with other health complications. 

Pregnant women with preeclampsia often experience the following symptoms:

• Persistent headache
• Pain in the upper stomach
• Nausea
• Vomiting
• Swelling in the hands and face
• Sudden weight gain
• Problems breathing
• Vision problems like blurry vision or changes in eyesight

You can experience preeclampsia while you are pregnant and not have any symptoms. That’s why you need to have regular checkups during your pregnancy so your doctor can monitor your blood pressure. 

In rare cases, women can experience postpartum preeclampsia and develop preeclampsia after giving birth. Postpartum preeclampsia can occur in women who did not experience preeclampsia while they were pregnant. Most cases of postpartum preeclampsia are diagnosed within 48 hours of delivery. However, the condition can take up to six weeks to develop.

You may be more at risk of developing high blood pressure during your pregnancy if you have one or more of the following risk factors:

• You are experiencing your first pregnancy
• You had chronic kidney disease or high blood pressure before becoming pregnant
• You are over the age of 40
• You have diabetes
• You experienced high blood pressure or preeclampsia during a previous pregnancy
• You are African American
• You are carrying more than one baby
• You have a family history of pregnant women who experienced preeclampsia
• You have lupus or thrombophilia (a disorder that can cause blood clots)
• You became pregnant through in vitro fertilization, donor insemination, or egg donation

Pregnant women should have regular prenatal visits with their doctor to monitor their and their baby’s health. You should let your doctor know about any health problems you experience, especially if you have symptoms of high blood pressure. 

Early treatment for high blood pressure while pregnant can reduce your chances of developing more severe health complications. Your doctor can also make other recommendations to help you stay healthy during your pregnancy. 

Your doctor will check your blood pressure during prenatal visits. If you record a high blood pressure, which is 140/90 or higher, your doctor will likely order additional tests, especially if you are in the 20th week of your pregnancy or later. 

These tests might include blood tests and urine tests to check for any protein in your urine, an indicator of preeclampsia. 

If you have preeclampsia, the condition usually clears up once you deliver your baby. For milder cases of gestational hypertension or preeclampsia, your doctor may wish to have you monitored in an outpatient facility or a hospital. Your doctor may also ask you to track your baby’s movements via a kick count and measure your blood pressure at home. 

If you experience high blood pressure during pregnancy, you will need to visit your doctor at least once per week and, in some cases, twice per week until you reach the 37th week of your pregnancy. At that point, your doctor may recommend inducing delivery. They may also ask you to have your baby earlier than 37 weeks if they feel that your baby’s health may be at risk. 

If you have a more severe case of preeclampsia, you will likely be admitted to a hospital. Your doctor may encourage inducing labor at 34 weeks. They may also administer medications intended to lower your blood pressure and reduce your chances of having a seizure.