In order to compare the vaginal microflora of women in prolonged pregn
ancy with that of women who delivered at term, samples for quantitativ
e aerobic and anaerobic microbiological culture were collected from 10
0 women at 42 weeks of gestation and from 60 women at term. The occurr
ence of lactobacilli-dominated flora was similar in women at term and
women with prolonged pregnancy. However, non-hydrogen-peroxide-produci
ng lactobacilli (p < 0.01) were significantly more common and Peptostr
eptococci species (p < 0.05) significantly less common in postterm wom
en as compared with term controls. In postterm women, Candida albicans
was more common (p < 0.001) in microfloras dominated by non-hydrogen-
peroxide-producing lactobacilli than in floras dominated by hydrogen-p
eroxide-producing lactobacilli. The ecosystem of the vagina in asympto
matic postterm women was disrupted concerning the composition of lacto
bacilli as compared with term controls.