Comparison of urinary and recombinant follicle-stimulating hormone in in vitro growth, maturation, and fertilization of mouse preantral follicles

ObjectiveTo compare the effects of urinary and recombinant follicle-stimulating hormone (FSH) on follicular development, oocyte maturation, and fertilization.DesignProspective randomized animal study.SettingUniversity-based research laboratory.Animal(s)Normal (C57BL/6xDBA2) F1 mice.Intervention(s)Collection of preantral follicles by mechanical dissection, in vitro growth (IVG) with urinary or recombinant FSH (100 mIU/mL), in vitro maturation (IVM), and fertilization.Main Outcome Measure(s)During IVG, follicle diameter and antral formation were evaluated. The number of cells per follicle was evaluated at the end of IVG. The 17β-estradiol measurements were performed from conditioned media. After IVM, mucification and oocyte maturation rates were estimated and mature oocytes were fertilized.Result(s)No differences were observed in the antral formation rate of either group. Antral follicles in the urinary FSH group, however, showed a higher diameter but a lower number of cells per follicle than those in the recombinant FSH group. The level of 17β-estradiol was also higher in the recombinant FSH group. The rate of mature oocytes developing into metaphase I or II was statistically significantly higher in the recombinant FSH group than in the urinary FSH group.Conclusion(s)Recombinant FSH provided better conditions than urinary FSH for the growth and development of mouse preantral follicles that could produce mature oocytes with fertilization capacity.