Clinical outcomes from mature oocytes derived from preovulatory and antral follicles: reflections on follicle physiology and oocyte competence

• Published in: Journal of assisted reproduction and genetics 2015-02, Vol.32 (2), p.255-261
• Main Authors: Fadini, Rubens, Coticchio, Giovanni, Brambillasca, Fausta, Mignini Renzini, Mario, Novara, Paola V., Brigante, Claudio, De Ponti, Elena, Dal Canto, Mariabeatrice
• Format: Article
• Language: English
• Subjects: Adult; Clinical outcomes; Embryo Implantation; Embryo Transfer - methods; Female; Fertilization in Vitro - methods; Gynecology; Human Genetics; Humans; In Vitro Oocyte Maturation Techniques; Logistic Models; Male; Medicine; Medicine & Public Health; Oocytes - physiology; Ovarian Follicle - physiology; Ovulation - physiology; Pregnancy; Pregnancy Rate; Reproductive Medicine; Reproductive Physiology and Disease; Retrospective Studies; Treatment Outcome
• ISSN: 1058-0468; 1573-7330
• DOI: 10.1007/s10815-014-0386-x

Purpose The aim of this retrospective study was to compare the competence of oocytes obtained from preovulatory and antral follicles. Methods Mature oocytes from preovulatory follicles were retrieved from women selected for standard IVF treatment (Group A). Mature oocytes from antral follicles were recovered from women undergoing hCG-primed in vitro maturation (IVM) treatment (Group B). Patients groups were matched for age, BMI, FSH, AMH and antral follicle count (AFC) values. In vivo matured oocytes from both groups were microinjected and resulting embryos were culture and selected on day 3 for embryo transfer. Results Oocyte pick-ups (OPU) were 315 and 204 in Groups A and B, respectively. Fertilization rates were comparable (72.8 and 75.9 %, respectively; P  = 0.137). In Group A, in which the average number of embryos transferred was higher, clinical pregnancy rates per OPU (37.5 %) and embryo transfer (38.4 %) were superior in comparison to Group B (27.0 %, P  = 0.013; 29.4 %, P  = 0.041; respectively). On the other hand, implantation rates (Group A, 23.7 %; Group B, 20.8 %) and proportions of babies born per transferred embryo (Group A, 19.5 %; Group B, 16.9 %) were similar ( P  = 0.528 and 0.332, respectively). Conclusions Overall, this suggests that oocyte competence is already achieved at the antral stage of follicle development.