title: Evaluation of the developmental potential of metaphase I oocytes from stimulated intracytoplasmic sperm injection cycles.
abstract: The objective of the present study was to evaluate the developmental potential and clinical application value of metaphase I (MI) oocytes obtained from stimulated intracytoplasmic sperm injection (ICSI) cycles. ICSI was performed on MI oocytes immediately after denudation (Group A), or on in vitro-matured (IVM) oocytes following culture; oocytes in culture were further divided into two groups, being cultured for either 3-5 h (Group B) or 24-28 h (Group C). Metaphase II oocytes from the same cycle(s) isolated for ICSI served as the control group (Group D). The rates of normal fertilisation, cleavage and high-quality embryos were compared among the four groups. High-quality embryos were transferred whenever possible, and pregnancy rates were evaluated. Results showed that normal fertilisation rates for Groups B, C and D were significantly higher than that of Group A (68.6%, 57.8%, 74.5% and 30.1%, respectively; P<0.01). The rate of high-quality embryos in Group B was comparable with Group D; the rate for Group C was significantly lower than that of the other groups (P<0.05). Two clinical pregnancies were achieved after transfer of embryos from IVM oocytes. In vitro maturation of MI oocytes for a short period of time may increase the number of available embryos; however, overnight in vitro culture of MI oocytes did not improve results.
authors.affiliation: Shandong Provincial Key Laboratory of Reproductive Medicine, Center for Reproductive Medicine, Provincial Hospital Affiliated to Shandong University, Jinan, 250021, People's Republic of China.
authors.forename: Mei
authors.initials: M
authors.lastname: Li
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.forename: Shui-Ying
authors.initials: SY
authors.lastname: Ma
authors.forename: Huai-Liang
authors.initials: HL
authors.lastname: Feng
authors.forename: Hui-Jun
authors.initials: HJ
authors.lastname: Yang
authors.forename: Ke-Liang
authors.initials: KL
authors.lastname: Wu
authors.forename: Wan-Xia
authors.initials: WX
authors.lastname: Zhong
authors.forename: Li
authors.initials: L
authors.lastname: Che
authors.forename: Zi-Jiang
authors.initials: ZJ
authors.lastname: Chen
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D004624:Embryo Transfer / Q000379:methods; D047108:Embryonic Development / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008677:Metaphase / Q000502:physiology*; D009865:Oocytes / Q000166:cytology / Q000502:physiology*; D011247:Pregnancy; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*; D013997:Time Factors