Aim: The aim of this study was to determine the prevalence of the Group B Streptococcus in 24 to 34-week pregnant women, with premature labor symptoms with and without the rupture of the amniotic sac.

Study design: A case-control study

Place and Duration: This study was conducted at Gynaecology and Obstetrics Unit at Dow University Hospital Karachi Pakistan from June 2020 to June 2021.

Methodology: All of the 60 women were 24 to 34 weeks pregnant and had premature labor symptoms. The women were divided into 2 groups based on whether the amniotic sac was intact or not. The Control group contained women with intact membranes and the case group contained women with ruptured membranes. From all the participants, Group B Streptococcus samples were collected from the vagina at the start of the study. These samples were then cultured. The demographic data and cultural information of all the women were compared in 2 groups. SPSS, chi-square test and t-test were used to analyze the data. A P-value less than 0.05 was considered significant.

Results: Both the groups showed no significant difference in maternal age with a p-value equal to 0.259, gestational age with a p-value equal to 0.725, gravidity with a p-value equal to 0.536, and history of previous premature deliveries with a p-value equal to 0.926. A total of 10 percent of the women with ruptured amniotic sacs resulted in positive Group B Streptococcus culture. On the other hand, 4 percent of the women with intact amniotic sacsresulted in positive Group B Streptococcus culture. The overall occurrence of Group B Streptococcus was almost 7 percent.

Conclusion: The prevalence of Group B Streptococcus was more in pregnant women with ruptured membrane/ amniotic sac than in pregnant women without ruptured membrane.

Keywords: Group B Streptococcus, premature labor, ruptured membrane, intact membrane, amniotic sac, culture test