Abstract 13: Group B Streptococcal Infection as a Cause of Stillbirth: A Cross-sectional Study from a Tertiary Care Center in India

Abstract Background: Group B Streptococcus (GBS) is a significant but underrecognized cause of stillbirth, particularly in low-and middle-income countries (LMICs) such as India, where diagnostic and surveillance practices remain limited. Aim: To estimate the prevalence of maternal GBS colonization and its correlation with fetal infection and placental histopathology. Methods: This cross-sectional study was conducted over 24 months at a tertiary carecenter. Maternal rectovaginal swabs and fetal samples(cord blood, lung aspirate) from 102 stillbirths (≥28 weeks or ≥1000 g) were cultured for GBS. Placental tissues were examined histologically. Associations were analyzed using chi-square and logistic regression. Results: Maternal GBS colonization was detected in 17.6% of stillbirth cases. GBS was isolated from 11.8% of amniotic fluid, 7.8% of cord blood, and 4.9% of lung aspirates. A significant maternal–fetal concordance was observed, with GBS-positive mothers showing 5.3 times higher odds of fetal GBS detection (p = 0.001). Placental inflammation was significantly more common in GBS-positive cases (p < 0.001). Conclusion: GBS is a major, yet often overlooked contributor to stillbirths, with strong maternal–fetal transmission and associated placental pathology. These findings emphasize the need for routine GBS screening during pregnancy and consideration of preventive strategies, including maternal GBS vaccination and the development of national screening guidelines, to reduce preventable stillbirths in low-resource settings.