Purpose: To assess the correlation of intrafollicular insulin, leptin and adiponectin levels with assisted reproductive technologies (ART) outcome.
Methods: This was a retrospective study of 46 patients undergoing in vitro fertilisation/intracytoplasmic sperm injection. Follicular fluid (FF) samples collected at oocyte retrieval were assayed for insulin, leptin and adiponectin levels using enzyme-linked immunosorbent assay, and correlations with ART outcome were analysed.
Results: There was no significant correlation between intrafollicular insulin, leptin and adiponectin levels. There was a significant difference in the concentration of insulin (P = 0.007), but not leptin or adiponectin, between pregnant (n = 20) and non-pregnant (n = 26) cycles. Only two pregnancies was observed in the 12 cycles in which the concentration of insulin was greater than 7 mU/l in FF, while 18 pregnancies was observed in the 34 cycles in which the concentration of insulin was less than 7 mU/l (P = 0.043). The significantly high concentration of insulin in FF was observed in non-pregnant cycles of patients with polycystic ovary syndrome (PCOS).
Conclusions: Our results suggest the possible involvement of intrafollicular insulin in folliculogenesis. Insulin resistance-related substances may affect the reproductive process in patients with PCOS.