| Excerpt from The WHO Reproductive Health Library | Published by Update Software Ltd. |
The Cochrane review found that metronidazole is effective against trichomoniasis during pregnancy yielding parasitological cure rates of around 90%; however, the drug may increase the risk of preterm birth.
Two trials with 842 women were identified. One trial carried out in the United States enrolled 617 asymptomatic women at between 16 and 23 weeks of gestation. Two grams of metronidazole was given at entry into the trial and 48 hours later, and then again after 14 days. This trial was stopped because metronidazole was found not to be effective in reducing preterm birth, and might even have increased it, in spite of achieving a high rate of parasitological cure. The second trial, carried out in South Africa, enrolled 376 women with more advanced pregnancy and with symptoms of trichomoniasis. One dose of 2 g metronidazole was used. This trial also showed high rate of parasitological cure but no discernible clinical effect on clinical outcomes.
Overall, the findings indicate that metronidazole is an effective treatment for symptomatic and asymptomatic trichomoniasis in pregnant women, but may be associated with increased risk of preterm delivery (relative risk: 1.8; 95% confidence interval: 1.2-2.7).
All adequately controlled trials which could be identified were included and analysed appropriately.
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