Effects of Metronidazole Therapy on Preterm Labor in Women


Regarding to prevalence of preterm labor and its consequences, there are different reports on relationship between bacterial vaginosis and preterm labor. This study was performed to evaluate the effect of etronidazole therapy on preterm labor in women with bacterial vaginosis. This randomized clinical trial was performed on 120 women suffering from bacterial vaginosis at 20-34 weeks of pregnancy, to evaluate the therapeutic effect of metronidazole to delay preterm labor in Shabih Khani maternity hospital in Kashan, Iran in 2002. Bacterial vaginosis was diagnosed based on clinical and laboratory findings. The patients were randomly divided into two groups. The patients in the case group received 500 mg metronidazole BID for 7 consecutive days, but the control group did not receive it. The demographic characteristics of the patients such as, pregnancy age, educational level and job of the spouse were similar at both case and control groups. Double-blind follow up of the patients at the whole stages of parturition and after delivery with respect to the de-livery method, infection, and fever was done by other practitioner besides the main researcher. The results were analyzed statistically by chi-square, and Fischer's exact tests. 420 patients entered the study, of whom 120 (28.6%) had bacterial vaginosis. The antibiotic and control groups were not significantly different for maternal age, job of the spouse, and education. No difference was observed in spontaneous preterm birth before 37 weeks of gestation in antibiotic-treated compared with control group. Treatment with metronidazole in symptomatic women with a bacterial vaginosis in the late second trimester does not decrease the incidence of preterm delivery.

Joesoef MR, Schmid G. Bacterial vaginosis. Clin Evid 2005; (13): 1968-78.

Morris M, Nicoll A, Simms I, Wilson J, Catchpole M. Bacterial vaginosis: a public health review. BJOG 2001; 108(5): 439-50.

Klebanoff MA, Hillier SL, Nugent RP, MacPherson CA, Hauth JC, Carey JC, et al. Is bacterial vaginosis a stronger risk factor for preterm birth when it is diagnosed earlier in gestation? Am J Obstet Gynecol 2005; 192(2): 470-7.

Hill GB. The microbiology of bacterial vaginosis. Am J Obstet Gynecol 1993; 169(2 Pt 2): 450-4.

Yen S, Shafer MA, Moncada J, Campbell CJ, Flinn SD, Boyer CB. Bacterial vaginosis in sexually experienced and non-sexually experienced young women entering the military. Obstet Gynecol 2003; 102(5 Pt 1): 927-33.

Klebanoff MA, Schwebke JR, Zhang J, Nansel TR, Yu KF, Andrews WW. Vulvovaginal symptoms in women withbacterial vaginosis. Obstet Gynecol 2004; 104(2): 267-72.

Marrazzo JM, Wiesenfeld HC, Murray PJ, Busse B, MeynL, Krohn M, et al. Risk factors for cervicitis among women with bacterial vaginosis. J Infect Dis 2006; 193(5): 617-24.

Hauth JC, Macpherson C, Carey JC, Klebanoff MA, HillierSL, Ernest JM, et al. Early pregnancy threshold vaginal pH and Gram stain scores predictive of subsequent preterm birth in asymptomatic women. Am J Obstet Gynecol 2003; 188(3): 831-5.

Amsel R, Totten PA, Spiegel CA, Chen KC, Eschenbach D, Holmes KK. Nonspecific vaginitis. Diagnostic criteria and microbial and epidemiologic associations. Am J Med 1983; 74(1): 14-22.

Klebanoff MA, Hauth JC, MacPherson CA, Carey JC, Heine RP, Wapner RJ, et al. Time course of the regressionof asymptomatic bacterial vaginosis in pregnancy with and without treatment. Am J Obstet Gynecol 2004; 190(2): 363-70.

Schwebke JR. Asymptomatic bacterial vaginosis: response to therapy. Am J Obstet Gynecol 2000; 183(6): 1434-9.

National guideline for the management of bacterial vaginosis. Clinical Effectiveness Group (Association of Genitourinary Medicine and the Medical Society for the Study of Venereal Diseases) [editorial]. Sex Transm Infect 1999; 75 Suppl 1: S16-8.

Centers for Disease Control and Prevention. Sexuallytransmitted diseases treatment guidelines 2002 [editorial]. MMWR Recomm Rep 2002; 51(RR-6): 1-78.

Leitich H, Bodner-Adler B, Brunbauer M, Kaider A, EgarterC, Husslein P. Bacterial vaginosis as a risk factor forpreterm delivery: a meta-analysis. Am J Obstet Gynecol 2003; 189(1): 139-47.

McDonald H, Brocklehurst P, Parsons J, Vigneswaran R. Antibiotics for treating bacterial vaginosis in pregnancy. Cochrane Database Syst Rev 2003; (2): CD000262.

Carey JC, Klebanoff MA, Hauth JC, Hillier SL, Thom EA,Ernest JM, et al. Metronidazole to prevent preterm delivery in pregnant women with asymptomatic bacterial vaginosis. National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units. N Engl J Med 2000; 342(8): 534-40.

McDonald HM, O'Loughlin JA, Vigneswaran R, Jolley PT, Harvey JA, Bof A, et al. Impact of metronidazole therapy on preterm birth in women with bacterial vaginosis flora (Gardnerella vaginalis): a randomised, placebo controlled trial. Br J Obstet Gynaecol 1997; 104(12): 1391-7.

Leitich H, Brunbauer M, Bodner-Adler B, Kaider A, Egarter C, Husslein P. Antibiotic treatment of bacterial vaginosis in pregnancy: a meta-analysis. Am J Obstet Gynecol 2003; 188(3): 752-8.

Okun N, Gronau KA, Hannah ME. Antibiotics for bacterial vaginosis or Trichomonas vaginalis in pregnancy: a systematic review. Obstet Gynecol 2005; 105(4): 857-68.

Guise JM, Mahon SM, Aickin M, Helfand M, Peipert JF, Westhoff C. Screening for bacterial vaginosis in pregnancy. Am J Prev Med 2001; 20(3 Suppl): 62-72.

Morales WJ, Schorr S, Albritton J. Effect of metronidazole in patients with preterm birth in preceding pregnancy and bacterial vaginosis: a placebo-controlled, double-blind study. Am J Obstet Gynecol 1994; 171(2): 345-7; discussion 348-9.

McGregor JA, French JI, Parker R, Draper D, Patterson E, Jones W, et al. Prevention of premature birth by screening and treatment for common genital tract infections: results of a prospective controlled evaluation. Am J Obstet Gynecol 1995; 173(1): 157-67.

Kurkinen-Räty M, Vuopala S, Koskela M, Kekki M, Kurki T, Paavonen J, et al. A randomised controlled trial of vaginal clindamycin for early pregnancy bacterial vaginosis. BJOG 2000; 107(11): 1427-32.

Kekki M, Kurki T, Pelkonen J, Kurkinen-Räty M, Cacciatore B, Paavonen J. Vaginal clindamycin in preventing preterm birth and peripartal infections in asymptomatic women with bacterial vaginosis: a randomized, controlled trial. Obstet Gynecol 2001; 97(5 Pt 1): 643-8.

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Bacterial vaginosis preterm labor metronidazole

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Moniri R, Behrashi M. Effects of Metronidazole Therapy on Preterm Labor in Women. Acta Med Iran. 47(3):181-184.