Global Antimicrobial Resistance Trends in Group B Streptococcus Isolates From Pregnant Women: Systematic Review and Meta-Analysis.

Maternal colonization with Group B Streptococcus (GBS) is associated with a high risk of serious infections during pregnancy. Also, the emerging resistance of GBS isolates to commonly used antibiotics has become a serious concern. This study aimed to provide a systematic review and meta-analysis of worldwide data on the prevalence of antimicrobial resistance of GBS in pregnant women to establish a better understanding of more effective antibiotic agents. A systematic literature search was performed in PubMed, Web of Science, and Scopus databases up to January 31, 2025. Statistical analysis was performed using the meta and metaphor packages in R, and sources of heterogeneity were evaluated using I2. The potential for publication bias was explored using Egger's and Begg's tests. A total of 169 eligible studies were included. The highest rate of resistance was associated with tetracycline (77.8%), while the lowest rates were found for vancomycin (0.59%), penicillin (0.7%), ampicillin (1%), and cefazolin (1.34%). The global resistance rates to penicillin, erythromycin, vancomycin, and clindamycin exhibited a gradual increasing trend in the 2021-2024 periods compared with other periods. The results highlighted the low levels of resistance to ampicillin and penicillin for pregnant women without an allergy history and cefazolin and vancomycin for those with an allergy history. However, given the increasing resistance trends and the high prevalence of resistance to clindamycin and erythromycin, these antibiotics should be recommended after antibiotic susceptibility testing.