Maternal infectious morbidity following multiple courses of betamethasone

Objective: the beneficial effects of antepartum corticosteroids on the reduction of morbidity and mortality in the premature neonate have been amply demonstrated. The NIH consensus statement has, therefore, endorsed their use in women at risk from pre-term delivery between 14 and 34 weeks gestation. Patients at persistent risk of pre-term delivery may receive multiple weekly courses. However, increased susceptibility to infection is a well-recognized complication of prolonged high-dose steroid therapy. We examined infectious morbidity among women exposed to three or more courses of betamethasone. Methods and outcome measures: thirty-seven patients at risk of pre-term delivery who received three or more courses of betamethasone (median = 6; range 3-10) and 74 normal controls, matched for maternal age, route of delivery and year of delivery were included in the study. Data on medical care provided to study and control patients between 24 weeks gestation and 6 weeks postpartum were retrieved from centralized medical records. Incidences and types of infections were compared by Chi-square and Fisher's exact test, as appropriate. Only infections diagnosed at least 1 week after betamethasone therapy was initiated were included. Patients with pre-existing conditions predisposing to infections morbidity were excluded. Results: twenty-four of 37 patients (64.8%) exposed to betamethasone vs. 13 of 74 (17.5%) controls developed infectious diseases (P < 0.001). Symptomatic lower urinary tract infections occurred in 13 of 37 (35.1%)) and two of 74 (2.7%) in the study and control groups, respectively (P < 0.001). Serious bacterial infections were found in nine of 37 (24.3%) vs. none of 74 (0%) patients, respectively (P < 0.001). These included sepsis (n = 2), pneumonia (n = 4), pyelonephritis (n = 2), and cholangitis (n = 1). Eight of nine serious infections occurred in patients exposed to five or more weekly courses of betamethasone. Postpartum endometritis related to Caesarean delivery was found in five of 37 patients (13.5%) vs. seven of 74 (9.4%), respectively (P = NS). Conclusions: Three or more courses of antepartum betamethasone in women at risk of pre-term delivery are associated with substantial infectious maternal morbidity. The excess morbidity consisted mainly of bacterial infections, some of which were associated with systemic and potentially life-threatening infections.