Successful delivery after the transfer of twice-vitrified embryos derived from in vitro matured oocytes: a case report
Hashimoto, S.; Murata, Y.; Kikkawa, M.; Sonoda, M.; Oku, H.; Murata, T.; Sugihara, K.; Nagata, F.; Nakaoka, Y.; Fukuda, A.; Morimoto, Y.
Human Reproduction 22(1): 221-223
2007
ISSN/ISBN: 0268-1161 PMID: 16966349 DOI: 10.1093/humrep/del354
Accession: 013019193
We report here the first case of successful pregnancy and delivery after the blastocyst transfer of twice-vitrified embryos produced following in vitro maturation (IVM) and ICSI. The patient received 5000 IU hCG on day 12 of the treatment cycle, and oocyte retrieval was carried out 36 h after hCG injection. A total of 22 immature oocytes were obtained. Following incubation for 26 h in IVM medium, 15 oocytes (68.2%) reached metaphase II stage. In total, 13 oocytes (86.7%) were fertilized after ICSI with the husband's sperm, and 11 embryos at the pronuclear stage and two cleaved embryos on day 2 were vitrified because of thin endometrial thickness. Eight cryopreserved embryos at the pronuclear stage were warmed and cultured until the day 3 stage. Three embryos were transferred, and three embryos were twice vitrified. Unfortunately, these transferred embryos did not implant. Three twice-vitrified embryos were rewarmed and cultured until the day 5 stage, and two embryos were transferred. The second transfer attempt of twice-vitrified embryos resulted in the full-term delivery of a healthy infant. This case report demonstrates that twice-vitrified embryos, developed using an IVM protocol, retain the developmental competence for full-term, healthy infants.