Different morphology and proliferative ability of cumulus and granulosa cells originating from cystic follicles aspirated from stimulated in vitro fertilization patients

Objective To investigate the morphology and proliferative ability of cumulus and granulosa cells (GCs) originating from cystic follicles and normal-sized follicles after ovarian stimulation. Design Granulosa cells, cumulus cells, and follicular fluid (FF) were aspirated from cystic follicles and normal-sized follicles from the same ovary. Morphology and proliferative ability of cumulus and GCs were assessed by Giemsa stain and thimidine incorporation, respectively. Cell proliferation was assessed in medium or FF originating from cystic follicles or normal-sized follicles. Results An oocyte was found in 40% of the cystic follicles versus 68% in the normal-sized follicles. Changes in dispersion and adhesion properties were observed in cystic versus normal aspirated corona cumuli complex. Proliferative ability was consistently lower in GCs originating from cystic follicles versus normal-sized follicles. Proliferation of GCs originating from normal-sized follicles or cystic follicles was inhibited or increased when grown in FF from cystic follicles or FF from normal-sized follicles, respectively. Differences in embryo quality were significantly in favor of oocytes originating from normal-sized follicles. Although the fertilization rate of those oocytes appeared to be higher, the difference was not of statistical significance. Conclusions Inhibition of GC proliferation in FF from cystic follicles can be reversed by incubating cells in FF from normal-sized follicles. We conclude that factors in the FF may affect cell proliferation.