Chronic hypertension with related drug treatment of pregnant women and congenital abnormalities in their offspring: a population-based study.

Chronic hypertension (CH) is a common chronic disease and occurs frequently in pregnant women. The teratogenic/fetotoxic effect of certain antihypertensive drugs has been shown. The objective of this study was to investigate the association between pregnant women with CH and the possible risk of congenital abnormalities (CAs) among their offspring. The prevalence of medically recorded CH in the prenatal maternity logbook was compared between 1030 pregnant women who later had offspring with CA (case group) and 1579 pregnant women with CH who later delivered newborn infants without CA (control group). Control newborn infants were matched to cases in the population-based data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities during 1980-1996. Of 23 different CA groups with informative offspring, esophageal atresia/stenosis was a greater risk in pregnant women with CH (adjusted odds ratios with 95% confidence intervals: 3.1, 1.4-6.8). In conclusion, a higher risk of esophageal atresia/stenosis was found in the offspring of pregnant women with severe CH, which could not be explained by related drug treatments. This finding requires confirmation or lack thereof by future studies.