In-vitro maturation of human oocytes from regularly menstruating women may be successful without follicle stimulating hormone priming

This prospective randomized study investigated whether the developmental potential of in-vitro matured (IVM) human oocytes is improved by follicle stimulating hormone (FSH) priming before aspiration. Normally cycling women were recruited among couples referred for in-vitro fertilization or intracytoplasmic sperm injection because of male factor and/or tubal disease. In the first experiment, 20 women were randomly allocated to either no stimulation (n = 10) or stimulation for 3 days with rec-FSH (Gonal-F, Serono) at a fixed dose of 150 IU/day from day 3 (n 10), The oocytes were aspirated when the follicle(s) was observed to be 10 mm and matured in vitro for 36 h, In experiment 2, 12 women received rec-FSH (150 IU/daily) from day 3, In five patients stimulation was given for 3 days and aspiration performed as in the first experiment; the remaining seven patients continued stimulation until follicles were 10 mm in diameter and aspiration was performed 72 h later, All the oocytes were cultured for 48 h, FSH priming did not increase the number of oocytes obtained per aspiration and did not improve on maturation to metaphase II, cleavage rate or embryo development. The implantation potential of IVM embryos may be improved by maturation for 36 h compared to 48 h, In the first experiment, five out of 20 patients (25%) obtained a clinical pregnancy with an implantation rate of 15% (5/33), One has delivered a healthy boy and three pregnancies are ongoing beyond 32 gestational weeks. In the second experiment, an implantation rate of 7% and a single pregnancy (8%) was obtained, with delivery of a healthy girl.