Antihypertensive drug use during pregnancy: a population based study

Purpose. The study aimed at assessing if the European guideline on the use of antihyper-tensive drugs (AD) in pregnancy are followed in clinical practice. We also evaluated the association between the use of non-recommended drugs and individual characteristics.
Methods. This study analyzed a cohort of 86 171 singleton deliveries occurring between 2009-2010 in the Lombardy region, Italy. Women with first prescription of AD during pregnancy were considered as incident users. Methyldopa, labetalol and nifedipine were considered as “recommended drugs”; all other AD were considered as “non-recommend-ed”. Odds Ratio and 95% confidence intervals were estimated.
Results. Among the 1009 patients (1.2%) exposed to AD during pregnancy, 675 (66.9%) were incident users. Among the incident users, 31% received non-recommended drugs; this proportion decreased to 18% among women who started treatment in the third tri-mester. Women with at least four concomitant diseases had an elevated risk of receiving non-recommended drugs in pregnancy (OR 2.68; 95% CI 1.10-6.73).
Conclusions. Exposure to recommended antihypertensives increased during pregnancy. Nevertheless, a fraction of users that continued or began treatment with non-recom-mended medications was still present.