Abstract:

Objective To retrospectively analyze the colonization of group B streptococcus (GBS) in patients with gestational diabetes mellitus (GDM), and to explore the risk factors for GBS colonization in GDM patients and their impact on pregnancy outcome. Methods A total of 2 777 GDM patients were enrolled and divided into the GBS-negative group (2 672 cases, including 1 275 vaginal deliveries and 1 397 cesarean sections) and the GBS-positive group (105 cases, including 61 vaginal deliveries and 44 cesarean sections) according to GBS colonization status. General datas and pregnancy outcome were compared between the two groups. Binary Logistic regression analysis was used to identify risk factors for GBS colonization in late pregnancy GDM patients. Results There were no statistically significant differences in maternal age, gravidity, parity, history of abortion, body mass index at delivery, gestational weight gain, prenatal care in our hospital, fasting blood glucose, blood glucose at each time point of oral glucose tolerance test, gestational week at delivery and the incidence of complicated bacterial vaginosis, premature rupture of membranes, scarred uteru and pregnancy complications between the two groups (all P>0.05). The proportion of complicated vulvovaginal candidiasis (VVC) was higher in the GBS-positive group than that in the GBS-negative group (P<0.05). Among women with vaginal delivery, the incidence of meconium-stained amniotic fluid was significantly higher in the GBS-positive group than that in the GBS-negative group (P<0.05).There were no significant differences in intrapartum fever, preterm birth, acute chorioamnionitis, postpartum hemorrhage, the incidence of fetal distress between the two groups (P<0.05). Among pregnant women who delivered by cesarean section, the incidence of acute chorioamnionitis was higher in the GBS positive group than that in the negative group (P<0.05), while there were no significant differences in the incidence of fecal contamination of amniotic fluid, preterm birth, postpartum hemorrhage and fetal distress between the two groups. Among neonates delivered vaginally or by cesarean section, the proportion of admission to the neonatal intensive care unit was higher in the GBS-positive group than that in the negative group (P<0.05). There were no significant differences in neonatal birth weight, the incidence of small for gestational age infants, macrosomia infants and neonatal respiratory distress syndrome between the two groups (P>0.05), and there was no case of neonatal GBS infection in either group. There was significant difference in the overall distribution of causes of cesarean section between the two groups (P<0.05), and the proportion of cesarean section performed due to fetal distress and acute chorioamnionitis was higher in the GBS-positive group than that in the GBS-negative group. Logistic regression analysis showed that complicated VVC was an independent risk factor for GBS colonization in late pregnancy in GDM women (P<0.05). Conclusion Pregnancy complicated with VVC can increase the risk of GBS colonization in pregnant women with GDM. Standardized management of GDM pregnant women, completed screening for GBS colonization during pregnancy, and targeted intrapartum antibiotic intervention are of great significance for improving maternal and neonatal outcomes.

Key words: Streptococcus agalactiae, diabetes, gestational, peripartum period, pregnancy outcome, risk factors