The review, published in The Cochrane Library, found women were no more likely to conceive when taking oral antioxidants and that there was limited information about potential harms. Around a quarter of couples planning a baby are thought to have some degree of difficulty conceiving.
A couple may be considered to have fertility problems if they have been trying to conceive for over a year with no success.
The reported prevalence of sub-fertility has increased significantly over the past 20 years, especially in the western world.
The researchers stated that women undergoing fertility treatment often take dietary supplements, including antioxidants, to try to increase their chances of becoming pregnant. The researchers analysed data from 28 trials involving a total of 3,548 women attending fertility clinics.
Investigators compared oral antioxidants, including combinations of antioxidants, pentoxifylline, N-acetyl-cysteine, melatonin, L-arginine, vitamin E, myo-inositol, vitamin C, vitamin D+calcium and omega-3-polyunsaturated fatty acids with placebo, with no treatment/standard treatment or with another antioxidant.
“There is no evidence in this review that suggests taking an antioxidant is beneficial for women who are trying to conceive,” said the lead researcher, Marian Showell, who is a specialist in obstetrics and gynaecology at the University of Auckland in New Zealand.