Prevalence of bacterial vaginosis and associated factors among women with preterm labour at Muhimbili National Hospital

Abstract

Bacterial vaginosis (BV), is a clinical syndrome resulting from replacement of the normal Hydrogen-peroxide (H2O2) producing Lactobacillus species with a higher concentration of anaerobic bacteria like Prevotella and Mobilincus sp, Gadnerella vaginalis and mycoplasma hominis. It is characterized by an increase of vaginal discharge with no obvious inflammation of the vagina. It represents about 40% to 60% of all cases of vaginitis, and it is thought to be more common than either Vulvovaginal candidiasis or Trichomoniasis.

BV is being associated with some serious obstetric risks like premature labor, low birth-weight, chorioamnionitis, and infection of the uterus post delivery. A wide range of prevalence has been reported in studies done in various parts of the world ranging from 6.8% to 28.5%, in pregnant women and 32.8% to 62.9% in non pregnant women.

This study was aimed at documenting the magnitude of BV among women with premature labor at the gestation age of least seven months pregnancy up to 36 weeks admitted at MNH labor ward and highlight the factors associated with it. A total of 206 patients were enrolled and the diagnosis of BV was done according to the clinical Amstel’s criteria.

The prevalence of BV in this study was found to be 39.2%. Women with history of abnormal vaginal discharge were fifteen times more likely to have BV as compared to those without abnormal vaginal discharge (OR 15, 95% CI 6.7-37, P= <0.001), while women who had no more than primary school education or housewives were over twice as likely to have BV (OR 2.07, 95% CI 1.18-3.66, P=0.012). HIV positive women had also a twofold increased risk of getting BV when compared to HIV negative women. (OR 2.76, 95%CI 1.02-7.46, P=0.046) There was a weak or no association between BV and such factors like low socio-economic status (being in the lowermost three wealth quintiles), history of recent antibiotics use, primigravidity, being in a polygamous marriage or being married or a history of previous miscarriage.

In conclusion, BV appears to occur in a great magnitude in patients with premature delivery in our setting. The study therefore recommends that medical practitioners develop a high suspicion index for pregnant women with abnormal vaginal discharges. Besides, policy makers should probably include screening and treatment for BV in the future policy of Antenatal care package.