Maternal asthma and risk of preeclampsia: a case-control study

To quantify the associations between asthma characteristics and the risk of preeclampsia.

In this case-control study, asthma history among 286 preeclampsia cases and 470 normotensive controls in Seattle was assessed by postpartum interview and medical record abstraction. OR and 95% CI were estimated using logistic regression. The sample size was adequate to detect unadjusted asthma history with ORs of > or =1.6 at a power of 80%.

After adjustment, women with a history of prepregnancy asthma diagnosis were not at increased preeclampsia risk (OR 0.94, 95% CI 0.58-1.52). Women experiencing asthma symptoms during pregnancy were more likely than pregnant nonasthmatics to have preeclampsia (OR 2.20, 95% CI 0.79-6.10). Those with long-term pre-pregnancy asthma and symptoms during pregnancy were at particularly increased risk (OR 9.09, 95% CI 1.02-81.6). Point estimates were generally higher after restriction to women withfull-term deliveries.

This analysis suggests that asthmatics, particularly those who are symptomatic during pregnancy, may be at higher risk of developing preeclampsia.