Group B streptococcus infection rate unchanged by gestational diabetes

Group B streptococcal colonization in pregnancy has been associated with adverse perinatal outcomes, including intra-amniotic infection, postpartum endometritis, and neonatal sepsis. We sought to determine whether gestational diabetes increases the risk of maternal and neonatal morbidity from group B streptococcal colonization.

Gestational diabetic and nondiabetic women who underwent vaginal or anogenital culture for group B streptococcus colonization in pregnancy were followed up for pregnancy outcome. Antibiotic prophylaxis was not routinely given. Major perinatal morbidity included intraamniotic infection, endometritis, and neonatal sepsis. Potential confounding variables included induction of labor, cesarean delivery, prematurity, maternal antibiotic use, and prolonged rupture of membranes.

We compared 446 gestational diabetic women to 1,046 nondiabetic women for outcome. Overall, 12% were colonized with group B streptococcus, with no difference in colonization rates between gestational diabetic (12%) and nondiabetic (12%) women. There were no differences in intraamniotic infection rates between gestational diabetic and nondiabetic women, whether group B streptococcus positive (16% compared with 13%) or group B streptococcus negative (10% compared with 11%). Likewise, endometritis did not differ (6-9%) regardless of diabetes or group B streptococcus status. Neonatal sepsis was higher in group B streptococcus-positive women overall (3% compared with 1%, odds ratio 3.71, 95% confidence interval 1.23, 10.81), but did not differ between diabetic and nondiabetic pregnancies.

Gestational diabetes does not alter the perinatal morbidity associated with group B streptococcal colonization in pregnancy.