brand logo

Am Fam Physician. 2023;108(4):411-412

Author disclosure: No relevant financial relationships.

Clinical Question

Should medication be prescribed for mild chronic hypertension in pregnancy?

Evidence-Based Answer

Evidence and expert opinion support treating mild chronic hypertension in pregnancy with approved antihypertensives. (Strength of Recommendation: B, randomized controlled trial [RCT].)

Evidence Summary

Evidence and expert opinion previously suggested that nonsevere chronic hypertension should not be treated during pregnancy because lowering the patient’s blood pressure too much could lead to placental hypoperfusion, fetal growth restriction, preeclampsia, or preterm birth.

In a 2022 RCT of 2,408 women with singleton pregnancies and mild chronic hypertension (i.e., blood pressure less than 160/100 mm Hg) before 23 weeks’ gestation, participants were randomized to receive antihypertensives approved for use in pregnancy (active treatment group) or no treatment unless they met criteria for severe hypertension (i.e., systolic blood pressure of 160 mm Hg or greater or diastolic blood pressure of 105 mm Hg or greater).1 The primary outcome was a composite of preeclampsia with severe features, medically indicated preterm birth at less than 35 weeks’ gestation, placental abruption, or fetal or neonatal death. Secondary outcomes included preeclampsia and preterm birth. The primary outcome was less common in the active treatment group (30.2% vs. 37.0% for no treatment; adjusted risk ratio = 0.82; 95% CI, 0.74 to 0.92; P < .001; number needed to treat [NNT] = 15).1 The active treatment group also had a lower incidence of preeclampsia (24.4% vs. 31.1%; risk ratio [RR] = 0.79; 95% CI, 0.69 to 0.89; NNT = 15) and preterm birth (27.5% vs. 31.4%; RR = 0.87; 95% CI, 0.77 to 0.99; NNT = 26).1

Already a member/subscriber?  Log In


From $165
  • Immediate, unlimited access to all AFP content
  • More than 130 CME credits/year
  • AAFP app access
  • Print delivery available

Issue Access

  • Immediate, unlimited access to this issue's content
  • CME credits
  • AAFP app access
  • Print delivery available
Purchase Access:  Learn More

Clinical Inquiries provides answers to questions submitted by practicing family physicians to the Family Physicians Inquiries Network (FPIN). Members of the network select questions based on their relevance to family medicine. Answers are drawn from an approved set of evidence-based resources and undergo peer review. The strength of recommendations and the level of evidence for individual studies are rated using criteria developed by the Evidence-Based Medicine Working Group (

The complete database of evidence-based questions and answers is copyrighted by FPIN. If interested in submitting questions or writing answers for this series, go to or email:

This series is coordinated by John E. Delzell Jr., MD, MSPH, associate medical editor.

A collection of FPIN’s Clinical Inquiries published in AFP is available at

Continue Reading

More in AFP

More in PubMed

Copyright © 2023 by the American Academy of Family Physicians.

This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP.  See permissions for copyright questions and/or permission requests.