Prevalence and Factors Influencing Colonization of Group B Streptococcus Among Expecting Mothers: A Cross-Sectional Study in Iringa, Tanzania

Background: Group B Streptococcus (GBS) is a main reason of maternal and newborn morbidity, underlying unusual pregnancy results including; sepsis, and primary-onset newborn illness. Information of delivering mother’s GBS colonization, linked factors, and drug exposure patterns is vital for notifying protective approaches and managing suitable prophylactic drugs during pregnant. Nevertheless, facts on GBS epidemiology in Tanzania are inadequate known. This research intended to come up with the prevalence, influencing factors, and drug exposure patterns of GBS colonization among expecting mothers in Iringa Tanzania. Methodology: An analytical cross-sectional study conducted to 131 expecting mothers with gestational age ≥37 weeks who underwent spontaneous vaginal delivery at Iringa Hospital. Low vaginal swabs were collected from delivering women, and umbilical swabs were obtained in their newborns immediately after birth. Specimens were cultured for GBS using standard microbiological techniques, and drug exposure testing was done using the Kirby–Bauer disk diffusion technique. Data were analyzed using SPSS version 27. Logistic regression analysis was employed to recognize influencing factors for GBS colonization, at CI of 95% with P-value of ≤ 0.05. Findings: Prevalence of delivering mothers GBS colonization was 23%. High blood pressure during pregnancy was independently influencing GBS colonization (adjusted odds ratio [AOR] = 11.43; 95% confidence interval [CI]: 2.72–48.04; p = 0.001). Multigravidas were also a significant predictor, with multigravidas being 15 times likely to be colonized than Primegravida (AOR = 15.13; 95% CI: 3.92–58.35; p < 0.001). High levels of antimicrobial resistance were observed to ceftriaxone (60%), gentamicin (57%), and erythromycin (47%), while most isolates remained susceptible to penicillin, cefotaxime, chloramphenicol, and vancomycin. Conclusion: Maternal GBS colonization among women delivering at Iringa Hospital is high, with hypertension during pregnancy and multigravidas identified as significant influencing factors. The substantial resistance to commonly used antibiotics insists the necessity for routine GBS screening, rational antibiotic use, as well as development of evidence-based recommendations for Tanzania’s prophylactic use of intrapartum antibiotic.