The vaginal flora of 214 women who had been referred, in labour, to Harare Maternity Hospital was investigated by examination of vaginal washings and of cervical and urethral swabs taken before and/or after delivery. Four groups of patients were studied: women who had a normal vaginal delivery (NVD), women who were referred because of meconium stained liquor (MSL), women with a history of prolonged rupture of membranes (PROM), and women who were delivered by cesarean section (CS). The first three groups had received no antibiotics during the 7 days preceding specimen collection, while specimens were collected from CS patients only after at least 48 hr of i.v. penicillin and chloramphenicol. T. vaginalis was identified in 19 percent of women, but was not associated with any specific patient group. Chlamydial antigen was detected in 13 percent of patients, but in only one patient (2 percent) in the MSL group. N. gonorrhoeae were isolated from 7 percent of women overall and 25 percent of the strains were penicillinase-producing. Gonococci were recovered significantly more frequently from the PROM patients than from NVD patients as were Group B streptococci and pigment-producing Bacteroides species. Lactobacilli were isolated from only 20 percent of women, despite the use of specific transport and isolation media for these organisms. Specimens from CS patients were taken after these had received parenteral penicillin and chloramphenicol and it was therefore not surprising to find major differences in their vaginal flora with a virtual absence of Gram-positive bacteria, and a high-rate of carriage of multi-resistant coliforms.(ABSTRACT TRUNCATED AT 250 WORDS)