Angiotensin-Converting Enzyme Inhibitors and the Risk of Congenital Malformations

Obstet Gynecol. 2017 Jan;129(1):174-184. doi: 10.1097/AOG.0000000000001775.


Objective: To examine the association between first-trimester angiotensin-converting enzyme (ACE) inhibitor exposure and the risk of overall major congenital, cardiac, and central nervous system malformations.

Methods: We used a cohort of completed pregnancies linked to liveborn neonates derived from Medicaid claims from 2000 to 2010. We examined the risk of malformations associated with first-trimester exposure to an ACE inhibitor. Propensity score-based methods were used to control for potential confounders including maternal demographics, medical conditions, exposure to other medications, and measures of health care utilization.

Results: The cohort included 1,333,624 pregnancies, of which 4,107 (0.31%) were exposed to ACE inhibitors during the first trimester. The prevalence of overall malformations in the ACE inhibitor-exposed pregnancies was 5.9% compared with 3.3% in the unexposed (unadjusted relative risk, 1.82; 95% confidence interval [CI] 1.61-2.06), of cardiac malformations was 3.4% compared with 1.2% (relative risk 2.95, 95% CI 2.50-3.47), and of central nervous system malformations was 0.27% compared with 0.18% (relative risk 1.46, 95% CI 0.81-2.64). After restricting the cohort to pregnancies complicated by chronic hypertension (both exposed and unexposed) and accounting for other confounding factors, there was no significant increase in the risk of any of the outcomes assessed. Relative risks associated with first-trimester ACE inhibitor exposure were 0.89 (95% CI 0.75-1.06) for overall malformations, 0.95 (95% CI 0.75-1.21) for cardiac malformations, and 0.54 (95% CI 0.26-1.11) for CNS malformations.

Conclusions: After accounting for confounders, among women with hypertension, exposure to ACE inhibitors during the first trimester was not associated with an increased risk of major congenital malformations.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Angiotensin-Converting Enzyme Inhibitors / therapeutic use*
  • Case-Control Studies
  • Central Nervous System / abnormalities*
  • Chronic Disease
  • Cohort Studies
  • Congenital Abnormalities / epidemiology*
  • Female
  • Heart Defects, Congenital / epidemiology
  • Humans
  • Hypertension / drug therapy
  • Hypertension / epidemiology
  • Pregnancy
  • Pregnancy Trimester, First
  • Prevalence
  • Propensity Score
  • Risk Factors
  • United States / epidemiology
  • Young Adult


  • Angiotensin-Converting Enzyme Inhibitors