The correlation of cumulus mucification patterns with oocyte maturation rate in vitro in FSH plus LH-primed IVM cycles: a prospective study

Purpose This prospective study was conducted to compare the oocyte maturation rate in vitro among four types of cumulus cell (CC) morphology, in dual gonadotropin-primed in vitro maturation (IVM) oocyte cycles. Methods Two-hundred and thirty cumulus-oocyte complexes (COCs) were retrieved from FSH + hCG-primed in vitro maturation cycles of 20 patients diagnosed with polycystic ovarian syndrome. The COCs that contained immature oocytes were classified into four groups according to their cumulus mucification patterns (dispersed, clumped, compacted or sparse) and their oocyte maturation rates were compared. Chi square test and Fisher's exact test were used as appropriate. Results Oocytes enclosed by dispersed and clumped CCs exhibited higher maturation rates than those with compacted and sparse patterns (P< 0.001). Conclusion In dual gonadotropin-primed IVM cycles, oocyte maturation rates are highest in those showing dispersed and clumped CC patterns.