Women who take antioxidants to help them conceive could be receiving no benefits from the supplements, research has shown.
Many women who undergo fertility treatment such as IVF take the pills in the belief that they might help them to get pregnant. These women contribute to the £300m spent on supplements in the UK each year.
Data from 3,548 women who attended fertility clinics found no evidence that supplements can actually increase conception or birth rates.
The Cochrane Library, which contains independent evidence to inform healthcare decision-making, published the findings of 28 reports on the effectiveness of treatments.
Lead researcher Dr Marian Showell, from the University of Auckland in New Zealand, said: “There is no evidence in this review that suggests taking an antioxidant is beneficial for women who are trying to conceive.”
Those women who took antioxidants were found to have been no more fertile than women who were given placebo tablets.
There was also no difference in supplement-taking women and those who received standard treatments, such as folic acid, which the NHS recommends for mothers in the early stages of pregnancy to prevent birth defects such as spina bifida.
However, women also suffered no harm from taking the pills according to fourteen trials which reported on adverse effects such as miscarriage and ectopic pregnancy.