The safety of calcium channel blockers in human pregnancy: a prospective, multicenter cohort study

Am J Obstet Gynecol. 1996 Mar;174(3):823-8. doi: 10.1016/s0002-9378(96)70307-1.


Objective: Our purpose was to examine the potential teratogenicity of calcium channel blockers.

Study design: Six teratogen information services prospectively collected and followed up 78 women with first-trimester exposure to calcium channel blockers. Pregnancy outcome was compared (by paired t text of chi2 analysis) with that of a control group matched for maternal age and smoking.

Results: There was no increase in major malformation (2/66=3.0% [calcium channel blockers] vs 0% [nonteratogenic controls], p=0.27); a fivefold increase was ruled out (baseline 2%, alpha = 0.05, beta = 0.20). The defects reported were attributable to maternal diabetes or coingestion of teratogens. The increase in preterm delivery 28% [calcium channel blockers] vs 9% [nonteratogenic controls], p=0.003), attributed to maternal disease by stepwise regression, was the most important factor responsible for the observed decrease in birth weight (mean -334 gm vs nonteratogenic controls, p=0.08).

Conclusion: This study suggests that calcium channel blockers do not represent a major teratogenic risk.

Publication types

  • Case Reports
  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Drug-Induced / etiology*
  • Adult
  • Birth Weight / drug effects
  • Calcium Channel Blockers / adverse effects*
  • Case-Control Studies
  • Chi-Square Distribution
  • Cohort Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Pregnancy
  • Pregnancy Outcome
  • Pregnancy Trimester, First
  • Prospective Studies
  • Regression Analysis


  • Calcium Channel Blockers