When high blood pressure (HBP) occurs during pregnancy and is not appropriately treated, it may negatively affect the health of both a mother and her baby during pregnancy, during delivery, or after delivery.1,2 High blood pressure, also known as hypertension (HTN), is a common and treatable health condition that occurs in 6% to 8% of all pregnancies among women ages 20 to 44 years in the United States.3,4 Complications from high blood pressure in pregnancy have become more common over the years, increasing from 5.3%* of delivery hospitalizations in 1993 to 9.1%* of delivery hospitalizations in 2014.5
For the mother, any hypertensive conditions, regardless of whether they were first diagnosed before (chronic HTN) or during (gestational HTN) pregnancy, may be linked to preeclampsiaExternal, eclampsiaExternal, stroke, pregnancy induction (speeding up the pregnancy to give birth), and placental abruption (the placenta separating from the wall of the uterus).1,6,7
For the baby, high blood pressure during pregnancy may affect the mother’s blood vessels—including the ones in the umbilical cord. When the blood vessels tighten, it becomes more difficult for the baby to get enough oxygen and nutrients to grow, and may result in preterm delivery (birth that occurs before 37 weeks of pregnancy) and low birth weight (when a baby is born weighing less than 5 pounds, 8 ounces).1,8
The good news is that this is a preventable issue. Poor outcomes may be detected early and/or avoided by increasing awareness, improving patient education and counseling, and providing appropriate treatment of any high blood pressure conditions before, during, or after pregnancy.1
*The percentages were calculated from a rate of 528.9 and 912.4 per 10,000 delivery hospitalizations.
What Should Women With High Blood Pressure Do Before, During, and After Pregnancy?
- Make a plan for pregnancy and talk with a health care provider about the following:
- Review medical conditions and current medicines. Women planning to become pregnant should discuss the need for any medicine before becoming pregnant and should make sure that they are taking only medicines that are necessary.15
- Find ways to reach and maintain a healthy weight through healthy eating and regular physical activity.1,15
- Engage early in regular prenatal careExternal and attend scheduled health care provider appointments.
- Discuss current medicines and which medicines are considered to be safe with a health care provider. Pregnant women should not stop or start taking any type of medicine that they need, including over-the-counter medicines, without first talking with a health care provider.15
- Keep track of blood pressure routinely by using a home blood pressure monitor Cdc-pdf[PDF-1.1M].External Contact a health care provider if blood pressure becomes higher than usual or if you experience any other signs and symptoms of preeclampsia (e.g., headache, dizziness, blurry vision).
- Continue to maintain a healthy lifestyle24 and track weight during pregnancy.
Types of High Blood Pressure Conditions Before, During, and After Pregnancy
High blood pressure can appear as many different conditions at various times before or during pregnancy. Your health care provider (doctor or nurse) should look for these conditions before and during pregnancy:5,1
In middle, late, or after pregnancy
Preeclampsia is defined as the new onset of high blood pressure (more than or equal to 140/90 mmHg)* on two occasions, at least 4 hours apart, or blood pressure readings of more than or equal to 160/110 mmHg in a woman with previously normal blood pressure. Learn about measuring blood pressure.
Risk factors for preeclampsia include:1
- Primiparity (giving birth for the first time)
- Preeclampsia during a previous pregnancy
- Chronic hypertension, chronic renal (kidney) disease, or both
- A history of thrombophilia (an abnormal condition that increases risk of blood clots in blood vessels)
- Multiple babies in one pregnancy (e.g., twins, triplets)
- In vitro fertilization
- A family history of preeclampsia
- Type I or type II diabetes
- Lupus (an autoimmune disease)
- Advanced maternal age (older than 40 years)
Preeclampsia is accompanied by protein in the urine (proteinuria) and possibly other organ problems. These problems could include:
- Low blood platelet count
- Abnormal kidney or liver function, resulting in sudden weight gain, swelling of face or hands, or upper abdominal pain
- Fluid in the lungs, causing difficulty breathing
- Changes in vision, including seeing spots or changes in eyesight
- Severe headache, nausea, or vomiting
Preeclampsia is typically diagnosed after 20 weeks of pregnancy and most often closer to delivery. It can occur together with another high blood pressure condition (e.g., chronic hypertension with superimposed preeclampsia). Preeclampsia affects 4% of pregnancies in the United States.1,10
On rare occasions, preeclampsia can occur after childbirth. This is a serious medical condition known as postpartum preeclampsia. It may develop in women without any history of preeclampsia.21 The symptoms for postpartum preeclampsia are similar to the symptoms and signs of preeclampsia, and it is typically diagnosed within 48 hours after delivery but can occur up to 6 weeks later.18
When preeclampsia is associated with seizures (without the mother having epilepsy), it is known as eclampsia.1,5
Before or in early pregnancy
In this condition, a woman develops high blood pressure (more than or equal to 140/90 mmHg)* before conception or before 20 weeks of pregnancy.1
Chronic Hypertension With Superimposed Preeclampsia
In early, middle, or late pregnancy
This condition happens when there are elevated blood pressure readings of less than 160/110 mmHg in pregnant women who develop protein in their urine after 20 weeks of pregnancy or before 20 weeks of pregnancy with protein in urine and accompanying organ problems.1
In middle or late pregnancy
This condition happens when high blood pressure (more than or equal to 140/90 mmHg)* happens only during pregnancy, without the presence of protein in the urine. It is typically diagnosed after 20 weeks of pregnancy or close to delivery. Gestational hypertension usually goes away after childbirth; however, affected women have an increased risk of developing chronic hypertension in the future.1,22
*In November 2017, the American College of Cardiology (ACC) and the American Heart Association (AHA) updated the definition of chronic hypertension to be more than or equal to 130/80 mmHg instead of more than or equal to 140/90 mmHg.23 This update may increase the number of women with high blood pressure conditions during or before pregnancy who will need additional attention from their health care providers.
For more information about high blood pressure during pregnancy, see the following resources:
- American College of Obstetricians and Gynecologists, Frequently Asked Questions on Preeclampsia and High Blood Pressure During PregnancyExternal
- American College of Obstetricians and Gynecologists, Hypertension in Pregnancy Cdc-pdf[PDF-2.1 MB]External
- American College of Obstetricians and Gynecologists, Postpartum Preeclampsia Checklist Cdc-pdf[PDF-550 KB]External
- Centers for Disease Control and Prevention, At A Glance 2016: Maternal Health: Advancing the Health of Mothers in the 21st Century Cdc-pdf[PDF-1 MB]
- Centers for Disease Control and Prevention, Division of Reproductive Health, Pregnancy Complications
- Centers for Disease Control and Prevention, Treating for Two: Medicine and Pregnancy
- March of Dimes, High Blood Pressure During PregnancyExternal
- National Institutes of Health. National Heart, Lung, and Blood Institute. High Blood Pressure External
- Preeclampsia FoundationExternal
- U.S. Preventive Services Task Force, Preeclampsia: ScreeningExternal