Antibiotics for treating bacterial vaginosis in pregnancy

Antibiotics are effective in the treatment of bacterial vaginosis in pregnancy but do not prevent preterm birth before 37 weeks, at least not after 20 weeks' gestation. After previous preterm birth, treatment may reduce the risk of preterm prelabour rupture of membranes and low birthweight.

A Cochrane review included 15 good quality trials with a total of 5 888 women (oral metronidazole: 5 trials; oral metronidazole plus erythromycin, oral clindamycin, ampicillin, vaginal metronidazole gel, 1 trial each; intravaginal clindamycin alone: 6 trials). Ten trials performed microbiological follow up and seven trials gave a second course of treatment (four only if bacterial vaginosis was not eradicated). Antibiotic therapy was effective at eradicating bacterial vaginosis during pregnancy (Peto odds ratio [OR] 0.17, 95% confidence interval [CI] 0.15 to 0.20; 10 trials, 4357 women). Treatment did not reduce the risk of preterm birth (PTB) before 37 weeks (OR 0.91, 95% CI 0.78 to 1.06; 15 trials, 5888 women), or the risk of preterm prelabour rupture of membranes (PPROM) (OR 0.88, 95% CI 0.61 to 1.28; four trials, 2579 women). However, treatment before 20 weeks' gestation may reduce the risk of preterm birth less than 37 weeks (OR 0.63, 95% CI 0.48 to 0.84; 5 trials, 2387 women). In women with a previous PTB, treatment did not affect the risk of subsequent PTB (OR 0.83, 95% CI 0.59 to 1.17, 5 trials, 622 women); however, it may decrease the risk of PPROM (OR 0.14, 95% CI 0.05 to 0.38) and low birthweight (OR 0.31, 95% CI 0.13 to 0.75; 2 trials, 114 women). In women with abnormal vaginal flora (intermediate flora or bacterial vaginosis) treatment may reduce the risk of PTB before 37 weeks (Peto OR 0.51, 95% CI 0.32 to 0.81; 2 trials, 894 women). Clindamycin did not reduce the risk of PTB before 37 weeks (Peto OR 0.80, 95% CI 0.60 to 1.05; 6 trials, 2406 women).

Another Cochrane review (abstract , review ) included one trial of antibiotic treatment for vaginal ureaplasma in pregnancy. 644 women received antibiotic treatment (erythromycin estolate, erythromycin stearate, clindamycin hydrochloride) and 427 received placebo. The incidence of low birthweight (< 2500 grams) was only evaluated for erythromycin (n=398) compared to placebo (n=427) and the difference was nonsignificant (RR 0.70, 95% CI 0.46–1.07). Data on preterm birth was not reported.

Ədəbiyyat

1. McDonald HM, Brocklehurst P, Gordon A. Antibiotics for treating bacterial vaginosis in pregnancy. Cochrane Database Syst Rev 2007 Jan 24;(1):CD000262.
2. Raynes-Greenow CH, Roberts CL, Bell JC, Peat B, Gilbert GL. Antibiotics for ureaplasma in the vagina in pregnancy. Cochrane Database Syst Rev 2004;(1):CD003767 (Last assessed as up-to-date: 24 July 2011).