Pregnancy-Induced Hypertension (High Blood Pressure in Pregnancy)

Types of high blood pressure in pregnancy

About a quarter to half of people with gestational hypertension go on to develop preeclampsia, especially if it starts before 32 weeks.

Symptoms

Gestational hypertension often has no symptoms and is found at prenatal checks. Warning signs that suggest preeclampsia include:

• severe or persistent headache
• vision changes: blurring, flashing lights, spots
• pain under the ribs on the right or in the upper middle abdomen
• nausea or vomiting in the second half of pregnancy
• sudden swelling of the face, hands or around the eyes
• rapid weight gain
• shortness of breath

Swelling of the feet and ankles alone is common in normal pregnancy and is not a reliable sign.

Risk factors

• first pregnancy
• preeclampsia in a previous pregnancy
• chronic hypertension, kidney disease, diabetes, lupus or antiphospholipid syndrome
• multiple pregnancy (twins or more)
• age over 35
• obesity (BMI over 30)
• IVF pregnancy
• family history of preeclampsia
• Black individuals face a higher risk, linked to social and structural factors

Diagnosis and monitoring

• blood pressure at every visit, and often home monitoring
• urine protein: dipstick and protein-to-creatinine ratio
• blood tests: platelets, liver enzymes, kidney function
• fetal monitoring: growth ultrasounds, amniotic fluid, Doppler blood flow and non-stress tests
• some centers use sFlt-1/PlGF blood tests to predict preeclampsia

Treatment

Gestational hypertension and preeclampsia without severe features

• close monitoring, often once or twice weekly, plus home blood pressure checks
• delivery recommended at 37 weeks
• bed rest is not recommended

Severe hypertension or severe features

• blood pressure medicines (such as labetalol, nifedipine or hydralazine) to bring readings below 160/110 quickly and prevent stroke
• magnesium sulfate to prevent seizures
• corticosteroids for the baby's lungs if delivery is likely before 34 weeks
• delivery at 34 weeks or sooner if the parent or baby is unstable

After birth

Blood pressure can stay high or even peak 3 to 6 days after delivery, and preeclampsia can first appear after birth. Blood pressure should be checked within 3 to 10 days after delivery. Most people's blood pressure returns to normal within 12 weeks.

Prevention

• low-dose aspirin from 12 to 28 weeks (ideally before 16 weeks) for people at high risk, or with more than one moderate risk factor, as recommended by your obstetric provider
• calcium supplements in people with low dietary calcium intake
• healthy weight before pregnancy and controlling chronic conditions
• early and regular prenatal care

Long-term health

Hypertension in pregnancy is a warning sign for future heart health. People who had it have a higher lifetime risk of chronic high blood pressure, heart disease, stroke and kidney disease. Yearly blood pressure checks and heart-healthy habits are recommended after pregnancy.

Frequently asked questions

What is pregnancy-induced hypertension?

It is high blood pressure, 140/90 or higher, that starts after 20 weeks of pregnancy in someone whose blood pressure was normal before. It includes gestational hypertension and preeclampsia, which also involves protein in the urine or organ effects.

What is the difference between gestational hypertension and preeclampsia?

Both involve new high blood pressure after 20 weeks. Gestational hypertension has no protein in the urine or organ damage. Preeclampsia adds protein in the urine or signs of organ involvement, such as abnormal liver or kidney tests, low platelets, headaches or vision changes.

What are the warning signs of preeclampsia?

Warning signs are a severe headache that will not go away, vision changes, pain in the upper right or middle abdomen, nausea or vomiting late in pregnancy, sudden swelling of the face or hands, rapid weight gain and shortness of breath. Seek care immediately.

Does pregnancy-induced hypertension go away after birth?

Usually yes. Blood pressure typically returns to normal within days to 12 weeks after delivery. It can peak a few days after birth, so checks are needed. Some people develop long-term high blood pressure and need ongoing care.

Can pregnancy-induced hypertension harm the baby?

Yes. It can reduce blood flow to the placenta, leading to poor growth, low amniotic fluid, early delivery and, rarely, placental abruption or stillbirth. Careful monitoring and timely delivery greatly reduce these risks.