Acute and chronic respiratory diseases in pregnancy: Associations with spontaneous premature rupture of membranes.

Objective. To examine whether acute and chronic respiratory diseases are associated with an increased risk of spontaneous premature rupture of the membranes (PROM). Methods. We used the 1993-2004 National Hospital Discharge Survey data of singleton deliveries in the USA (N = 41 250 539). The International Classification of Diseases Ninth Revision was utilized to identify acute (acute upper respiratory diseases, viral/bacterial pneumonia, and acute bronchitis/bronchiolitis) and chronic (chronic bronchitis and asthma) respiratory conditions and spontaneous PROM. All analyses were adjusted for potential confounders. Results. The incidence of PROM was 5%, and rates of acute and chronic respiratory conditions were 2.1 and 9.5 per 1000 pregnancies, respectively. Chronic bronchitis was associated with a reduced risk of PROM (RR 0.39, 95% CI 0.31, 0.48). Asthma was significantly associated with PROM at preterm (RR 1.15, 95% CI 1.14, 1.17) and term (RR 1.27, 95% CI 1.23, 1.30). Stratification by race showed that acute upper respiratory disease was associated with preterm PROM in whites (RR 1.90, 95% CI 1.71, 2.11) and blacks (RR 6.76, 95% CI 5.67, 8.07). Viral/bacterial pneumonia was associated with preterm PROM in blacks and term PROM in both races. Asthma was associated with term PROM in blacks but not whites. Conclusions. Acute respiratory diseases and asthma during pregnancy are associated with spontaneous PROM, with substantially stronger association among blacks than whites. We speculate that timely diagnosis and treatment, coupled with closely mentoring of pregnant women may help reduce the rate of PROM and associated complications. [ABSTRACT FROM AUTHOR]