Neonatal group B streptococcal infection - Results of 33 months of universal maternal screening and antibioprophylaxis.

Objective: To assess the efficacy and pitfalls of a protocol of generalized screening for group B Streptococcus (GBS) and intra-partum treatment of al l carriers in a clinical setting. Design: A descriptive study and compariso n with an historical group. Setting: A tertiary perinatal center. Populatio n: All women attending prenatal care in our center and delivered after 37 w eeks were eligible. Study period ranged from January 1994 to September 1996 . Comparison group consisted in deliveries of years 1992 and 1993. Methods: Vaginal cultures were performed at 36 weeks on non-selective medium follow ed by intra-partum treatment of all carrier mothers. Rate of carriage, inci dence of neonatal GBS sepsis, influence of risk factors and the reasons for failures were analysed. Comparison was made with an historical group. Stat istical analysis was performed using a Chi-square test. Results: There were 5374 term deliveries during the study. 3906 were screened (72.7%) and 559 of them found positive for GBS (14.3%). We observed 46 early-onset GBS dise ases (0.86% of term-births). 43.5% of infections occurred in babies born fr om mothers without risks factors: at delivery. Negative GBS cultures at sam pling accounted for 43.5% of protocol failures. Comparison of the incidence of early-onset GBS disease with the previous two years showed a significan t drop (1.45-0.86%, P<0.05). Conclusions: Our protocol revealed feasible an d effective in reducing the incidence of early-onset GBS disease. Improveme nts must be studied particularly as to the predictive value of screening cu ltures. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.