The role of ovarian follicular antioxidants and reactive oxygen species in human female reproduction

Infertility affects about 15% of couples and in many cases the aetiology is easily identified. Aetiological diagnosis is more difficult in about 15% of females, when infertility is related to less clearly identifiable factors such as luteal phase deficiency and endometriosis. It has been suggested that oxidative stress may interfere with female fertility, analogous to the situation in males, and may play a role in some cases of unexplained fertility. This study was designed to evaluate the role of follicular fluid oxidative stress in female reproduction. Follicular fluid total antioxidant capacity (TAC) and TAC loss, indirect measures of oxidative stress, were related to early reproductive outcome, specifically oocyte recovery, fertilisation, and subsequent embryo viability after 3 days in culture. Follicular TAC was assayed in a pilot study using two methods - the trolox equivalent antioxidant capacity (TEAC) assay and the ferric reducing/antioxidant power (FRAP) assay - to determine the optimum assay for TAC. Good correlation was observed between the assays. The FRAP assay methodology was robust, easier, cheaper and quicker to perform, and was therefore used to determine follicular fluid TAC in the rest ... (continues)