This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To determine whether supplementary oral antioxidants improve outcomes for couples with an idiopathic subfertile male partner who were referred to a subfertility clinic and may or may not be undergoing assisted reproduction techniques (ART) such as in vitro fertilisation (IVF), intrauterine insemination (IUI) or intra cyclic sperm injection (ICSI) as compared to placebo.

The main questions to be asked in this review:
1.to determine whether supplemented oral antioxidants improve outcomes for couples with male factor who were referred to a subfertility clinic and may or may not be undergoing assisted reproduction techniques (ART) such as in vitro fertilisation (IVF), intrauterine insemination (IUI) or intra cyclic sperm injection (ICSI) as compared to placebo;

2.to determine whether different types, doses and combined antioxidant therapy given to men have varying effects in this setting.