Genital infections and risk of premature rupture of membranes in Mulago Hospital, Uganda: a case control study

BACKGROUND: Inflammatory mediators that weaken and cause membrane rupture are released during the course of genital infections among pregnant women. We set out to determine the association of common genital infections (Trichomonas vaginalis, syphilis, Neisseria gonorrhea, Chlamydia trachomatis, Group B Streptococcus, Bacterial vaginosis, Herpes Simplex Virus Type 2 and candidiasis) and premature rupture of membranes in Mulago hospital, Uganda. METHODS: We conducted an unmatched case–control study among women who were in the third trimester of pregnancy at New Mulago hospital, Uganda. The cases had PROM and the controls had intact membranes during latent phase of labour in the labour ward. We used interviewer-administered questionnaires to collect data on socio-demographic characteristics, obstetric and medical history. Laboratory tests were conducted to identify T. vaginalis, syphilis, N. gonorrhea, C. trachomatis, Group B Streptococcus, Bacterial vaginosis, Herpes Simplex Virus Type 2 (HSV-2) and candidiasis. Logistic regression models were used to estimate the odds ratios (OR) and 95 % CI of the association between genital infections and PROM. RESULTS: There was an association between PROM and abnormal vaginal discharge (OR = 2.02, 95 % CI 1.10–3.70 and AOR = 2.30, 95 % CI 1.18–4.47), presence of candidiasis (OR = 0.27, 95 % CI 0.14–0.52 and AOR = 0.22, 95 % CI 0.10–0.46) and T. vaginalis (OR = 2.98, 95 % CI 1.18–7.56 and AOR = 4.22, 95 % CI 1.51–11.80). However, there was no association between PROM and presence of C. trachomatis (OR = 2.05, 95 % CI 0.37–11.49) and HSV-2 serostatus (OR = 1.15, 95 % CI 0.63–2.09). Few or no patients with Bacterial vaginosis, Neisseria gonorrhoea, Group B streptococcus or syphilis were identified among the cases and controls. Co-infection of Trichomoniasis and candidiasis was not associated with PROM (AOR = 1.34, 95 % CI 0.16–11.10). Co infection with T. vaginalis and C. trachomatis was associated with PROM (OR = 3.09, 95 % CI 1.21–7.84 and AOR = 4.22, 95 % CI 1.51–11.83). CONCLUSION: Trichomonas vaginalis alone, T. vaginalis with C. trachomatis co-infection and abnormal per vaginal discharge were found as risk factors for PROM. There was no association of HSV-2 serostatus, syphilis, N. gonorrhea, C. trachomatis, Group B Streptococcus and Bacterial vaginosis with PROM. Candidiasis seemed to have a protective effect on PROM.