Prevalence and risk factors for group B streptococcal colonization in pregnant women in northern India

Abstract

Background: Group B Streptococci are a constituent of the normal vaginal bacterial microflora. During pregnancy there are optimal conditions for GBS multiplication in the vagina, which may have serious consequences for both the mother and her child. Aims: To study the prevalence of Group B Streptococcal colonization in pregnant women in Eastern U.P and antibiogram of the isolates (GBS) with a view to determine the pattern of antibiotic resistance. Study design: Observational cross-sectional study. Methods: 300 pregnant women admitted at tenn gestation or with preterm labour were recruited in the study. Swabs were taken from the lower one third of vagina and the anorectal region and then placed in Todd-Hewitt Broth, an enrichment media for GBS and later subcultured on blood agar. It was then examined for beta haemolytic colonies. The Chi-square test and Fisher's exact test were used to compare the two groups. P values <0.05 were considered statistically significant. Results: The culture positivity rate of GBS was 2%. Significant association was found with increasing age, gravidity (Age>30 years, p<0.012; Gravida>3, p<0.03), and higher socioeconomic status (p<0.007). No significant association found between GBS colonization and level of education, urban/rural area and gestational age. Prevalence of GBS in PROM was 5.6% and in preterm labour 3.3%. All the isolates were sensitive to ampicillin and resistant to gentamicin. Conclusions: GBS colonization among pregnant women was significantly correlated with age, parity and socioeconomic status. In pregnancy GBS colonization can cause premature rapture of membranes and pretenn labour. Keywords: Group B streptococcus. Pregnancy, Puerperium