Vitamins improve pregnancy rates of subfertile women in small study

Women receiving fertility treatment are more likely to become pregnant if they take multivitamin supplements, reports a UK pilot study.

The study recruited 56 subfertile women, between 19 and 40 years old. Participants were split in to two groups at random. One group was given multivitamin, or multiple micronutrient (MMN), supplements once daily and the other group folic acid, a government-recommended supplementation proven to reduce the risk of certain birth defects (the MMN supplements also contained folic acid). After four weeks both groups received standard drug fertility treatment with either clomiphene citrate (Clomid) or human menopausal gonadotrophin (HMG).

The fertility rate was increased in women receiving MMN supplements compared with the women receiving folic acid only. Sixty percent of women (18 of the 30 patients) on MMN fell pregnant versus 25 percent of women (11 out of 28) of women on folic acid. Viable pregnancies beyond three months were determined by detection of a fetal heart beat.

Furthermore, women on MMN supplementation had significantly fewer attempts to achieve pregnancy compared to women on folic acid. Fifteen women taking MMN became pregnant at their first attempt, whereas only two women receiving folic acid alone had the same outcome.

Lead author of the study Dr Rina Agrawal, consultant obstetrician and gynecologist and associate professor in reproductive medicine at the University of Warwick, said: 'All women considering pregnancy should take a specifically formulated prenatal micronutrient supplement to optimise their chances of conception'.

However, Catherine Collins, principal dietician at St George's Hospital NHS Trust, told the Daily Telegraph: 'As this study was of women with conception problems there's no evidence to suggest every woman considering pregnancy should take them'.

Other scientists have pointed out that this study is very small and a much larger study on a more diverse group of women is required to establish the possible benefits of MMN supplementation. Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield said: 'We should acknowledge that this is a relatively small number of patients and the study would need to be repeated in a larger trial before we could be certain of the results'.

This study was conducted at University College London and the Royal Free Hospital and published in Reproductive BioMedicine Online. A larger study is underway.