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Published on: May 11, 2017
Can in vitro maturation overcome cycles with repeated oocyte maturation arrest? A classification system for
Safak Hatirnaz1, Alper Başbuğ2, Ebru Hatirnaz1
1IVF-IVM Center, Medicana International Hospital, Samsun, Turkey.
Objective:
To investigate the role of gonadotropin-stimulated and human chorionic gonadotropin (hCG) -primed in vitro oocyte maturation (IVM) in cases of repeated in vitro fertilization (IVF) failure due to various forms of oocyte maturation arrest (OMA).
Methods:
Retrospective cohort study.
Results:
In all, 63 women with IVF failure due to OMA were evaluated in this study. According to the Hatirnaz & Dahan classification, 11 (17.5%) women were OMA type 1, 22 (34.9%) were OMA type 2, 0 were OMA type 3, 11 (17.5%) were OMA type 4, and 19 women were OMA type 5 (30.1%). Fewer oocytes were retrieved in the IVM than in the IVF cycles. No embryos were produced from oocytes collected in the IVM cycles of women with OMA types 1, 2, and 4. In the OMA type 5 group, 9 (47.4%) day 2 embryos and 6 (31.6%) day 3 embryos were obtained. The difference between the groups was statistically significant (P = 0.001, P = 0.002, respectively). Single day 3 embryo transfer was performed for the six patients with OMA type 5 but no clinical pregnancies occurred.
Conclusions:
Follicle-stimulating hormone-stimulated and hCG-primed IVM does not improve oocyte maturation, developmental potential, or pregnancy rates of women with OMA. Future studies directed to re-establishing normal cytoskeletal architecture and machinery, and resumption of meiosis may be beneficial for obtaining mature oocytes.
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