Severity of asthma and perinatal outcome

Our objective was to determine the impact of asthma and its severity, as determined by medication requirements, on perinatal outcome.

A case-controlled study was conducted. Among 30,940 live births at Long Beach Memorial Medical Center Women's Hospital, 183 deliveries occurred between Jan. 1, 1985, and Dec. 31, 1990, that were coded for the diagnosis of asthma. Eighty-one that required the chronic use of medications to control their disease were identified. Thirty-one patients were steroid dependent and 50 were non-steroid-medication dependent. A control group was randomly selected (excluding maternal transports), and selected perinatal variables were compared between groups.

When compared with controls, steroid-dependent asthmatics were at significantly increased risk for gestational (1.5% vs 12.9%) and insulin-requiring diabetes (0% vs 9.7%). Preterm delivery and preterm premature ruptured membranes occurred significantly more often in both asthmatic groups. Overall cesarean section rate was significantly increased in the non-steroid-medication-dependent asthmatic group when compared with controls (56.0% vs 30.0%). Delivery by primary cesarean section was significantly more common in the steroid-dependent group (38.7% vs 19.2%), and a strong trend was noted among the non-steroid-medication-dependent patients (34.0% vs 19.2%). Cesarean delivery for fetal distress was also more common in these two asthmatic groups. Neonates born to both groups of asthmatic pregnant women were significantly more likely to be of birth weight < 2500 gm but did not have an increased frequency of intrauterine growth restriction. No significant differences in low 5-minute Apgar scores were found; however, neonates born to both steroid-dependent and non-steroid-medication-dependent asthmatics were significantly more likely to be admitted to the neonatal intensive care unit (39.0% and 22.0% vs 7.7%). Preterm delivery and low birth weight were complications observed significantly more often in the steroid-dependent asthma group when compared with the non-steroid-medication-dependent group (54.8% vs 14.0% and 45.2% vs 14.0%).

Perinatal outcome is compromised in the pregnancy complicated by chronic medication-dependent asthma. The extent is variable and is associated with disease severity, as measured by medication requirements.