Abstract

Objective: To determine the frequency of Streptococcus agalactiae (GBS) colonization in pregnant women in Porto Alegre, Brazil, and to evaluate obstetric, perinatal outcomes and antimicrobial resistance.
Methods: This prospective cohort study enrolled 1003 pregnant women and vaginal and rectal  swabs  were  collected  between  the  35th  and  37th  gestational  weeks  and  cultured  in  selective  medium.  In  case  of  GBS,  the  patients  received  chemoprophylactic  treatment  during labor. This study was approved by the Ethics Research Committee of the institution.The level of significance was set at p<0.05.
Results: The prevalence of GBS infection was 9.27% (95%CI: 7.5%-11.1%). There was an association between premature membrane rupture (PROM) and GBS maternal colonization. The antibiotic used was penicillin G in 86.4% of the cases. Neonates of mothers with GBS infection had lower gestational age at birth (p<0.05) and fetal length (p<0.05) than those of  mothers  without  GBS  colonization,  but  there  were  no  higher  rates  of  neonatal  ICU admission or birth weight differences Resistance to antimicrobial agent was found in 7.6% of the cases.
Conclusion:  Prenatal  screening  and  labor  management  have  been  adequate  to  avoid  invasive neonatal disease due to GBS infection. Randomized studies should be conducted to confirm whether GBS treatment during prenatal follow-up may reduce PROM rates and preterm deliveries.

Keywords

maternal infection, intrapartum prophylaxis, neonatal septicemia, group B Streptococcus, premature rupture of membranes, preterm delivery