Clinical question
How effective is vitamin supplementation in preventing spontaneous miscarriage?
Bottom line
There was no evidence to support the prophylactic use of any vitamins to prevent early miscarriage. Supplementing women with multivitamins with or without iron and/or folic acid or vitamin A, might decrease the risk of stillbirth. There was insufficient evidence to examine the effect of different combinations of vitamins on miscarriage and miscarriage-related outcomes.
Caveat
Some of the trials included in the review were at high risk of bias, either due to poor or unclear allocation concealment or large losses to follow-up. The data were also complicated by differing definitions of miscarriage.
Context
Miscarriage is a common complication of pregnancy that can be caused by a wide range of factors. Poor dietary intake of vitamins has been associated with an increased risk of miscarriage.
Cochrane Systematic Review
Balogun OO et al. Vitamin supplementation for preventing miscarriage. Cochrane Reviews, 2016, Issue 5. Art. No.: CD004073.DOI: 10.1002/14651858. CD004073.pub4. This review contains 40 studies involving 276,820 women and 278,413 pregnancies.
Cochrane Systematic Reviews for primary care practitioners
Developed by the Cochrane Primary Care Field, New Zealand Branch of the Australasian Cochrane Centre at the Department of General Practice and Primary Health Care, University of Auckland and funded by the Ministry of Health and New Zealand Doctor. PEARLS are meant for educational use and not to guide clinical care. New Zealanders can access the Cochrane Library free via www.cochrane.org.nz
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