A new study suggests that antioxidants do not improve a woman's chances of conceiving as previously suggested, according to researchers from the University of Auckland, New Zealand.
The study, published in The Cochrane Library, found that women who take oral antioxidants are no more likely to conceive and that there was "limited information" about potential harmful effects.
Other research has suggested that antioxidants could boost fertility within men.
A previous study, also from the University of Auckland, showed that partners of men who take antioxidants may be more likely to become pregnant.
The study authors say that around 25% of people planning to have a baby experience trouble conceiving and many take dietary supplements, such as antioxidants, to try and improve their chances of becoming pregnant.
However, the researchers say that there is no sufficient evidence that this is the case, and they add that many of the antioxidants taken are unregulated, with little evidence on their safety and effects.
The researchers conducted an analysis of data from 28 trials involving 3,548 women who were undergoing fertility treatment.
The duration of the fertility treatment ranged from 12 days to 2 years, and the age of the women ranged between 18 to 42.
The analysis of the trials showed that a variety of antioxidants were used in the fertility treatment process of some women.
These included individual doses or combinations of:
* Multiple micronutrients and Fertility Blend
* Vitamin E
* Vitamin C
Vitamin D and Calcium
* polyunsaturated fatty acids.
Results of the analysis showed that compared to women taking placebos or being given standard treatments including folic acid, there was no significant increase of women taking antioxidants becoming pregnant.