Background: Preterm birth (PTB) is a prevalent reason for fetal and neonatal mortality and morbidity, characterized by all births that occur prior to thirty-seven weeks of gestation. Aim:  This study aimed to examine the association between PTB and early-stage vaginal colonization with GBS, a significant reason for disease throughout pregnancy. Patients and methods: This was retrospective cohort research that included 100 electronic health records from March 2022 to March 2023 retrieved from Damanhur Medical National Institute and used in a single center. Regardless of their symptoms, all pregnant females underwent vaginal sampling for culture and Gram staining during the initial stages of pregnancy Results: The examination did not reveal any statistically significant correlation between Gestational age (GA) and GBS during the initial stages of pregnancy, overweight, maternal age, diabetes mellitus, thyroid disease, GDM, preterm PROM, term PROM, GA at delivery, birth weight, sex, Apgar score after 1 minute, Apgar score after five  minutes, NICU admission and neonatal Group B Streptococcus (GBS)  disease, while there has been a statistically significant correlation between nullipara and GBS during the initial stages of pregnancy (PTB below 34 weeks and PTB below 37 weeks, p < 0.05). Conclusion: This investigation demonstrated the association among PTB and group B streptococcal colonization in pregnant females and found that there was a significant correlation between PTB and GBS-positive during the initial stages of pregnancy, both PTB at less than thirty-four and at less than thirty-seven weeks of gestation. Also, there was a significant association between PTB and diabetes mellitus at less than thirty-seven weeks.