What is high blood pressure in pregnancy?
Blood pressure is the force of your blood pushing against the walls of your arteries as your heart pumps blood. High blood pressure, or hypertension, is when this force against your artery walls is too high. There are different types of high blood pressure in pregnancy:
- Gestational hypertension is high blood pressure that you develop while you are pregnant. It starts after you are 20 weeks pregnant. You usually don't have any other symptoms. In many cases, it does not harm you or your baby, and it goes away within 12 weeks after childbirth. But it does raise your risk of high blood pressure in the future. It sometimes can be severe, which may lead to low birth weight or preterm birth. Some women with gestational hypertension do go on to develop preeclampsia.
- Chronic hypertension is high blood pressure that started before the 20th week of pregnancy or before you became pregnant. Some women may have had it long before becoming pregnant, but didn't know it until they got their blood pressure checked at their prenatal visit. Sometimes chronic hypertension can also lead to preeclampsia.
- Preeclampsia is a sudden increase in blood pressure after the 20th week of pregnancy. It usually happens in the last trimester. In rare cases, symptoms may not start until after delivery. This is called postpartum preeclampsia. Preeclampsia also includes signs of damage to some of your organs, such as your liver or kidney. The signs may include protein in the urine and very high blood pressure. Preeclampsia can be serious or even life-threatening for both you and your baby.
What causes preeclampsia?
The cause of preeclampsia is not known.
Who is at risk for preeclampsia?
You are at higher risk of preeclampsia if you
- Had chronic high blood pressure or chronic kidney disease before pregnancy
- Had high blood pressure or preeclampsia in a previous pregnancy
- Have obesity
- Are over age 40
- Are pregnant with more than one baby
- Are African American
- Have a family history of preeclampsia
- Have certain health conditions, such as diabetes, lupus, or thrombophilia (a disorder which raises your risk of blood clots)
- Used in vitro fertilization, egg donation, or donor insemination
What problems can preeclampsia cause?
Preeclampsia can cause
- Placental abruption, where the placenta separates from the uterus
- Poor fetal growth, caused by a lack of nutrients and oxygen
- Preterm birth
- A low birth weight baby
- Damage to your kidneys, liver, brain, and other organ and blood systems
- A higher risk of heart disease for you
- Eclampsia, which happens when preeclampsia is severe enough to affect brain function, causing seizures or coma
- HELLP syndrome, which happens when a woman with preeclampsia or eclampsia has damage to the liver and blood cells. It is rare, but very serious.
What are the symptoms of preeclampsia?
Possible symptoms of preeclampsia include
- High blood pressure
- Too much protein in your urine (called proteinuria)
- Swelling in your face and hands. Your feet may also swell, but many women have swollen feet during pregnancy. So swollen feet by themselves may not be a sign of a problem.
- Headache that does not go away
- Vision problems, including blurred vision or seeing spots
- Pain in your upper right abdomen
- Trouble breathing
- If you are more than 37 weeks pregnant, your provider will likely want to deliver the baby.
- If you are less than 37 weeks pregnant, your health care provider will closely monitor you and your baby. This includes blood and urine tests for you. Monitoring for the baby often involves ultrasound, heart rate monitoring, and checking on the baby's growth. You may need to take medicines, to control your blood pressure and to prevent seizures. Some women also get steroid injections, to help the baby's lungs mature faster. If the preeclampsia is severe, you provider may want you to deliver the baby early.
Eclampsia can also cause seizures, nausea and/or vomiting, and low urine output. If you go on to develop HELLP syndrome, you may also have bleeding or bruising easily, extreme fatigue, and liver failure.
How is preeclampsia diagnosed?
Your health care provider will check your blood pressure and urine at each prenatal visit. If your blood pressure reading is high (140/90 or higher), especially after the 20th week of pregnancy, your provider will likely want to run some tests. They may include blood tests other lab tests to look for extra protein in the urine as well as other symptoms.
How is preeclampsia treated?
Delivering the baby can often cure preeclampsia. When making a decision about treatment, your provider take into account several factors. They include how severe it is, how many weeks pregnant you are, and what the potential risks to you and your baby are:
The symptoms usually go away within 6 weeks of delivery. In rare cases, symptoms may not go away, or they may not start until after delivery (postpartum preeclampsia). This can be very serious, and it needs to be treated right away.
- About Preeclampsia and Eclampsia (National Institute of Child Health and Human Development) Also in Spanish
- High Blood Pressure and Pregnancy (Mayo Foundation for Medical Education and Research) Also in Spanish
- Preeclampsia and High Blood Pressure During Pregnancy (American College of Obstetricians and Gynecologists) - PDF Also in Spanish
- Pregnancy-Induced Hypertension (American Academy of Family Physicians) Also in Spanish
- What Are the Symptoms of Preeclampsia, Eclampsia, and HELLP Syndrome? (National Institute of Child Health and Human Development) Also in Spanish
Diagnosis and Tests
- How Do Health Care Providers Diagnose Preeclampsia, Eclampsia, and HELLP Syndrome? (National Institute of Child Health and Human Development) Also in Spanish
- Magnesium Blood Test (National Library of Medicine) Also in Spanish
Treatments and Therapies
- What Are the Treatments for Preeclampsia, Eclampsia, and HELLP Syndrome? (National Institute of Child Health and Human Development) Also in Spanish
- HELLP Syndrome (American Academy of Family Physicians) Also in Spanish
- Pregnancy Complications: HELLP Syndrome (March of Dimes Birth Defects Foundation)
- Pregnancy Complications: Liver Disorders (March of Dimes Birth Defects Foundation) Also in Spanish
- What Are the Risks of Preeclampsia and Eclampsia to the Fetus? (National Institute of Child Health and Human Development) Also in Spanish
- What Are the Risks of Preeclampsia and Eclampsia to the Mother? (National Institute of Child Health and Human Development) Also in Spanish
- Genetics Home Reference: preeclampsia (National Library of Medicine)
- ClinicalTrials.gov: Hypertension, Pregnancy-Induced (National Institutes of Health)
- ClinicalTrials.gov: Pre-Eclampsia (National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Serum magnesium levels during magnesium sulfate infusion at 1 gram/hour versus 2 grams/hour...
- Article: Pre-eclampsia: pathophysiology and clinical implications.
- Article: Comparison of Choroidal Thickness in Preeclamptic, Healthy Pregnant, and Nonpregnant Women:...
- High Blood Pressure in Pregnancy -- see more articles