Chronic high blood pressure is common and very manageable in pregnancy, but it needs planning. Some of the most widely used blood pressure drugs — ACE inhibitors and ARBs — are not used in pregnancy, so ask your prescriber now how and when they will switch you. Do not stop anything on your own. Since the 2022 CHAP trial, ACOG has supported treating blood pressure in pregnancy to a goal below 140/90.
Blood pressure planning has a sequence
What counts as chronic hypertension
The CDC describes chronic hypertension as high blood pressure that was present before pregnancy or is diagnosed before 20 weeks of pregnancy. In pregnancy, high blood pressure is generally diagnosed at 140/90 mm Hg or higher on two readings at least four hours apart, and readings of 160/110 or higher are considered severe.
That definition matters for planning: if you already have a diagnosis, or you have been told your readings are “borderline” and to keep an eye on them, pregnancy is the moment to get clarity. Blood pressure that is first noticed at the initial prenatal visit is often actually long-standing.
Chronic hypertension is different from gestational hypertension (new high blood pressure after 20 weeks) and from preeclampsia, though it raises the risk of the latter. The CDC lists chronic hypertension, kidney disease, diabetes, autoimmune conditions such as lupus, and sleep apnea among preeclampsia risk factors.
Why control before pregnancy matters
The CDC lists the main risks of high blood pressure in pregnancy as preeclampsia, stroke, kidney problems, placental abruption, and cesarean delivery for the parent, and preterm birth, low birth weight, and poor growth for the baby. Preeclampsia affects about 2% to 8% of all pregnancies and is one of the leading causes of pregnancy-related death.
That list can be hard to read. Here is the reassuring side: these are risks that prenatal care is built to watch for, and well-controlled blood pressure with the right medication lowers them. The CDC’s own advice is straightforward — get blood pressure under control before conception, talk to your care team about which medicines are safe in pregnancy, and work toward a healthy weight if that is part of your picture.
The medication review: ACE inhibitors, ARBs, and what replaces them
This is the single most important preconception step for many people with chronic hypertension.
ACE inhibitors (drug names usually end in -pril, like lisinopril) and ARBs (names usually end in -sartan, like losartan) are among the most commonly prescribed blood pressure medicines. Their U.S. labels carry a boxed warning for fetal toxicity: drugs acting on the renin-angiotensin system “can cause injury and death to the developing fetus,” with the label instructing that the drug be discontinued as soon as possible when pregnancy is detected. The labels describe problems with fetal kidney function and low amniotic fluid with second- and third-trimester use.
ACOG’s practice bulletin on chronic hypertension in pregnancy (as summarized by American Family Physician) advises avoiding ACE inhibitors, ARBs, renin inhibitors, and mineralocorticoid receptor antagonists in pregnancy, and names labetalol and extended-release nifedipine as preferred options, with methyldopa and hydrochlorothiazide as other possibilities.
When to switch varies. Some prescribers prefer to change medication before you start trying; others, especially when an ACE inhibitor or ARB is protecting the kidneys, may plan a fast switch at the first positive test. What matters is that you leave the visit knowing which plan is yours. Other medications can be relevant too — for example, labetalol is generally avoided in people with asthma, which is worth mentioning if you have both (see asthma and pregnancy planning).
| Question to ask | Why |
|---|---|
| Is anything I take an ACE inhibitor, ARB, or similar drug? | Combination pills sometimes hide these ingredients. |
| Will you switch me before we start trying, or at a positive test? | Avoids a scramble in early pregnancy. |
| If I test positive on my current drug, who do I call, and how fast? | The label says to discontinue as soon as possible once pregnancy is detected — a known plan prevents delay. |
| What readings should make me call you? | Gives you clear thresholds instead of guesswork. |
Baseline tests before you conceive
ACOG’s guidance recommends evaluating people with chronic hypertension before pregnancy for organ effects and other conditions that need management, and notes that some tests are easier to interpret before pregnancy changes the body’s physiology. The American Family Physician summary lists a typical baseline:
- Complete blood count, liver enzymes, creatinine, electrolytes, and blood urea nitrogen.
- A spot urine protein-to-creatinine ratio (with a 24-hour urine test if it is elevated).
- An ECG or echocardiogram if there are signs of reduced heart function.
- Consideration of testing for secondary causes of high blood pressure, which the summary says are found in 11% to 14% of pregnant people with chronic hypertension.
These baselines are not busywork. If protein in the urine or a lab value changes later in pregnancy, your team needs to know what was already there before pregnancy to tell whether something new, like preeclampsia, is developing.
The CHAP trial and the 140/90 target
For years, many clinicians held off on medication in pregnancy until readings were quite high. The Chronic Hypertension and Pregnancy (CHAP) trial, published in 2022, tested that approach. It randomized 2,408 pregnant people with mild chronic hypertension either to treatment aiming for below 140/90 or to standard care that treated only if pressure exceeded 160/105.
The treated group had fewer serious outcomes — a combination of severe preeclampsia, medically indicated birth before 35 weeks, placental abruption, or fetal or newborn death: 30.2% versus 37.0%. Importantly, there was no significant difference in small-for-gestational-age babies, which had been the main worry about treating more aggressively. ACOG then issued a practice advisory supporting treatment to a goal below 140/90 in pregnancy.
For you, this means two things: your team may want your blood pressure lower than you expect, and it is reasonable to ask what target they are using.
Aspirin and preeclampsia prevention
The U.S. Preventive Services Task Force recommends low-dose aspirin (81 mg daily) after 12 weeks of pregnancy for people at high risk of preeclampsia, and lists chronic hypertension as a high-risk factor on its own. This is something your obstetric provider prescribes during pregnancy — not something to start while trying. It is a good question to put on your list for the first prenatal visit.
Home monitoring you can trust
The CDC encourages people with high blood pressure in pregnancy to track readings at home and contact their doctor about readings higher than usual or symptoms of preeclampsia. A home log started before pregnancy also gives your prescriber better information when choosing your medication.
- Use an upper-arm cuff in the right size for your arm.
- Check that the model is independently validated. The AMA-associated Validated Device Listing lets you filter for devices validated in pregnancy.
- Sit quietly for a few minutes first, feet flat, arm supported at heart level.
- Take readings at consistent times and write them down or use the device’s memory.
- Bring the cuff to an appointment once to compare it with the clinic’s reading.
Know the warning signs the CDC lists for preeclampsia: a headache that will not go away, vision changes, upper belly pain, nausea or vomiting, swelling of the face or hands, sudden weight gain, and trouble breathing. Some people have no symptoms at all, which is why scheduled checks matter.
The human side of planning with high blood pressure
Chronic hypertension often feels invisible — no symptoms, just numbers — until pregnancy suddenly makes it the center of every appointment. That shift can be jarring. A few things help:
- Bring a partner into the monitoring. They can help with readings, notice symptoms, and keep the postpartum checks going when you are exhausted.
- Look at the whole picture. Sleep apnea, diabetes, and kidney disease often travel with high blood pressure. If you snore heavily or wake unrefreshed, read sleep apnea and fertility.
- Plan for after birth too. The CDC notes that people who had high blood pressure in pregnancy have a higher risk of stroke and other problems after delivery. Postpartum blood pressure checks are part of the plan, not an afterthought.
Frequently asked questions
Can I get pregnant if I have high blood pressure?
Yes. Many people with chronic hypertension have healthy pregnancies. The CDC advises getting blood pressure under control before conception and reviewing all medicines with your care team, because some common blood pressure drugs are not used in pregnancy.
Should I stop lisinopril or losartan before trying to conceive?
Not on your own. ACE inhibitors and ARBs carry a boxed warning for fetal toxicity and are avoided in pregnancy, but stopping without a replacement can leave blood pressure uncontrolled. Ask your prescriber to plan the switch and tell you what to do if you test positive first.
What blood pressure medicines are used in pregnancy?
ACOG guidance names labetalol and extended-release nifedipine as preferred options, with methyldopa and hydrochlorothiazide as alternatives. Your prescriber will choose based on your health history.
What blood pressure target is used in pregnancy now?
After the 2022 CHAP trial, ACOG issued a practice advisory supporting treatment of chronic hypertension in pregnancy to a goal below 140/90 mm Hg.
Will I need aspirin during pregnancy?
Possibly. The U.S. Preventive Services Task Force recommends low-dose aspirin after 12 weeks for people at high risk of preeclampsia, including those with chronic hypertension. Your obstetric provider will decide whether and when to prescribe it.
Sources & guidance
- CDC: High Blood Pressure During Pregnancy
- American Family Physician: Managing Chronic Hypertension in Pregnant Women — ACOG Releases Updated Practice Bulletin (2019)
- American College of Cardiology: Does Treatment of Mild Chronic Hypertension During Pregnancy Improve Pregnancy Outcomes? The CHAP Study Results
- DailyMed: Lisinopril tablet prescribing information (boxed warning: fetal toxicity)
- U.S. Preventive Services Task Force: Low-Dose Aspirin Use for the Prevention of Preeclampsia (2021)
- Validated Device Listing (VDL): validated blood pressure monitors