The effect of bioidentical nanostructured progesterone in the in vitro culture of preantral follicles and oocyte maturation

This study evaluated the effects of bioidentical nanostructured progesterone alone or in association with human chorionic gonadotropin (hCG) on the in vitro survival and development of preantral follicles (experiment 1) and oocyte maturation (experiment 2). Bioidentical hormones have a molecular structure identical with that of endogenous hormones; nanostructured substances refer to those reduced to a nanoscale. In experiment 1, fragments of goat ovarian tissue were cultured for 7 days in α-MEM+ alone or supplemented with nanoprogesterone (MEM+ + P4) or P4 and hCG (MEM+ + P4 + hCG). In experiment 2, two mediums of oocyte in vitro maturation (IVM) were compared. Medium 1 consisted of TCM 199+ + LH, and medium 2 consisted of TCM 199+ with nanoprogesterone and hCG. The MEM+ + P4 + hCG treatment showed the lowest percentage of follicular survival after 7 days of culture. MEM+ + P4 and MEM+ + P4 + hCG treatments showed higher percentage of follicular activation than MEM+. In experiment 2, there were no differences between mediums 1 and 2 for all endpoints evaluated. In conclusion, the addition of nanoprogesterone is advisable for in vitro culture of preantral follicles and oocyte maturation. However, the association of nanoprogesterone with hCG causes the cellular death of initial follicles but shows efficacy in IVM.