Context: Bacterial vaginosis has been prospectively linked to various adverse reproductive and pregnancy related events. Objective: To determine the prevalence of bacteria vaginosis among first time antenatal clinic attendees in Northwest Nigeria. Study design, setting and subjects: A Cross sectional study conducted at the Antenatal clinic of the Ahmadu Bello University Teaching Hospital, Zaria, north-west Nigeria. A total of 228 consecutive booking clients were enrolled from April to June, 2008. Main outcome measures: Presence of at least three of the following: (i) thin, white homogenous discharge, (ii) clue cells on microscopy, (iii) pH of vaginal fluid >4.5 (iv) release of fishy odor on adding alkali (10% potassium hydroxide) or positive whiff test (Amsel’s criteria) and (v) relative proportion of bacteria morphotypes on gram staining (The Nugent score). Results: In all 220 (96.5%) clients concluded the study and were analyzed. Prevalence of bacteria vaginosis (BV) was 14.6% using the Nugent score. Prevalence of asymptomatic BV was 9.6%. Eleven (34.4%) of the clients with BV were symptomatic while 21 (65.6%) were asymptomatic. There was no significant difference in the prevalence of BV between symptomatic and asymptomatic women. Presence of clue cells on microscopy (χ2=10.5, p=0.001), absence of yeast cells (χ2=4.120, p=0.042) and isolation of Gardnerrella vaginalis (χ2=36.480, p=0.000) were significantly associated with BV. BV was more prevalent in the second trimester (81.3%) among parous women with low education, low economic status, in polygamous marriages, who had not used hormonal contraceptives or who were HIV positive. Amsel criteria method had a low sensitivity of 37.5% and a specificity of 70.7%, a positive predictive value of 17.9% and negative predictive value of 86.9%. Conclusion: It is necessary to screen for BV in high risk women with previous untoward events like low birth weight and preterm delivery especially in the second trimester.
Victor D Ajayi, Habib M Sadauki, Abdullahi Randawa, Bamgboye M Afolabi