Treatment options for bacterial vaginosis in patients at high risk of preterm labor and premature rupture of membranes

Aim: To estimate the efficacy of different therapeutic modalities on proven cases of bacterial vaginosis (BV) in patients at high risk of preterm labor and premature rupture of membranes. Methods: This was a longitudinal prospective comparative study set in the antenatal outpatient clinic of the department of Obstetrics and Gynecology, Faculty of Medicine, Assiut University, Assiut, Egypt. Four hundred and sixty-eight patients with a clinical picture of threatened preterm labor or at high risk of premature rupture of membranes in the third trimester were screened for BV. Positive BV was diagnosed in 156 patients. They were randomly classified into four equal groups according to the line of medical treatment. The treatments were: (i) oral metronidazole, (ii) clindamycin vaginal cream, (iii) oral clindamycin, or (iv) metronidazole vaginal suppositories. The effects of medical treatment on Amsel's criteria as well as maternal and fetal outcomes were measured. Results: Based on Amsel's criteria, 156 patients (33.3%) were diagnosed with BV. There was a significant disappearance of vaginal discharge, with decreased percentages of pH > 4.5, positive amine test, and clue cells after treatment of BV in the four groups without any statistically significant difference between them. There were variable effects of the different treatments on increasing birthweight values, admission to neonatal intensive care units, and prolongation of the gestational age. Some maternal adverse effects have been recorded. There were significant improvements of the outcomes for oral metronidazole and clindamycin compared with outcomes for intravaginal metronidazole and clindamycin. Conclusions: Metronidazole and clindamycin achieve nearly equivalent cure rates when administered orally or vaginally in patients at high risk of preterm labor and premature rupture of membranes. Oral metronidazole is considered the drug of choice in treating BV due its high cure rate, better outcomes, and low cost.