Anaphylaxis in the obstetric patient: analysis of a statewide hospital discharge database.

BACKGROUND: Previous reports of anaphylaxis during pregnancy typically have involved single institutions and a few cases.
OBJECTIVE: To describe the epidemiologic features of anaphylaxis in women who gave birth in Texas.
METHODS: Statewide public use hospital discharge data for 2004 and 2005 provided by the Texas Department of State Health Services were accessed. Diagnoses and procedures in this data set were recorded using International Classification of Diseases, Ninth Revision, Clinical Modification codes. The records of women who delivered a neonate and simultaneously had a diagnosis of anaphylaxis were selected for study. The prevalence of maternal anaphylaxis noted at the time of delivery of the neonate and the 95% Wilson's confidence interval were calculated. The International Classification of Diseases, Ninth Revision, Clinical Modification E codes were examined to determine the possible anaphylactic trigger. Finally, the impact of 4 selected maternal comorbidities and complications on length of stay was assessed.
RESULTS: A total of 19 maternal anaphylaxis cases were identified. The prevalence was 2.7 cases per 100,000 deliveries (95% confidence interval, 1.7-4.2 cases per 100,000 deliveries). Penicillins and cephalosporins were the anaphylactic trigger in 11 of the patients. Five patients were emergent admissions. There were no maternal deaths. Most of the patients (14 [74%]) delivered by cesarean section. Patients who had 1 or more of 4 selected comorbidities or complications had a median length of stay of 5 days, whereas those patients free of these conditions had a median length of stay of 3 days (P = .07, exact Wilcoxon rank sum test).
CONCLUSIONS: Anaphylaxis during pregnancy is a rare event. In this large case series, we found that beta-lactam antibiotics were the most common triggers of anaphylaxis.