- To investigate whether colonization with GBS in a previous pregnancy is associated subsequently with adverse obstetric and perinatal outcomes. A retrospective study was undertaken comparing pregnancy complications of patients with and without colonization with GBS in a previous pregnancy from 1988 to 2006. Women with a positive GBS culture in the current pregnancy, women lacking prenatal care and multiple gestations were excluded from the analysis. Adverse obstetric and perinatal outcomes including premature rupture of membranes, intrapartum fever, chorioamnionitis and perinatal mortality. Out of 184,266 singleton deliveries, 230 (0.12%) were of patients with a positive GBS culture in their previous pregnancy. Previous GBS colonization was not found to be associated with adverse pregnancy outcomes such as PROM (9.1 vs. 6.8%; P = 0.16), intrapartum fever (1.3 vs. 2.2%; P = 0.72) and chorioamnionitis (1.3 vs. 0.8%; P = 0.29). GBS colonization in a previous pregnancy is not associated with adverse pregnancy outcomes in the current pregnancy.