Discontinuation of antihypertensive drug use during the first trimester of pregnancy and the risk of preeclampsia and eclampsia among women with chronic hypertension.

Objective: The goal of this study was to investigate the association between the discontinuation of antihypertensive medication use during the first trimester of pregnancy and the risk of preeclampsia and eclampsia.

Study Design: We conducted a nested case-control approach within a cohort that was reconstructed from the linkage of 3 databases. To be included in the study, women had to match the following criteria: (1) between 15-45 years old on the first day of gestation, (2) covered by Québec's Drug Insurance Plan for at least 12 months before and during pregnancy, (3) exposed to an antihypertensive drug on the first day of gestation, and (4) have had a delivery. Multivariate conditional logistic regression models were used to estimate the risk.

Results: Adjusting for confounders, the odds ratio was 0.66; 95% confidence interval, 0.27-1.56.

Conclusion: Our finding does not support the presence of a statistically significant association between antihypertensive discontinuation during the first trimester of pregnancy and the risk of preeclampsia and eclampsia.