Successful delivery after the transfer of twice-vitrified embryos derived from in vitro matured oocytes: A Case Report

Abstract

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.

Successful pregnancy after recryopreservation by vitrification of one blastocyst developed from a frozen embryo obtained by PESA: case report

“…This way, many embryos are wasted after the transfer of the best ones in a cryopreseved cycle, which could either be used in further cycles or donated to research. Our case corroborates previous finding [5] and emphasizes the pregnancy potential of vitrified blastocysts generated after in vitro culture of frozen/thawed cleavage stage embryos.…”

“…It has already been reported that human embryos twice frozen or vitrified can result in successful deliveries ( [4,5]). Moreover, one case report describes the birth of twins after the transfer of 2 vitrified-rewarmed blastocysts generated from frozen cleavage stage embryos [6].…”

A closed system supports the developmental competence of human embryos after vitrification

“…Blastocysts that were scored at least 3AA without C by Gardner's criteria were vitrified as good blastocyst. The endometrium was prepared using methodology described previously [9], modified by administration of GnRH agonist (600 μg/day, Suprecur® nasal solution 0.15 %; Mochida Pharmaceutical, Tokyo, Japan) for 3 weeks followed by incremental doses of oral oestradiol valerate (Progynova®; Bayer Schering Pharma, Zürich, Switzerland) from 1 to 4 mg for 2 weeks. After using ultrasonography to confirm the endometrial thickness to be more than 8 mm, 6 mg/day chlormadinone acetate (Lutoral®; Shionogi & Co., Osaka, Japan) was administered.. Progesterone (Progeston depot® 125 mg; Fuji Pharma Co., Toyama, Japan) was administered intramuscularly on the day of embryo transfer, with two additional doses after conception.…”

Perinatal outcome of twice-frozen-thawed embryo transfers: a clinical follow-up study

“…Conversely, only limited published data are available for FET with human embryos that were frozen-thawed twice (6,7). To our knowledge, the description of successful live births derived from refrozen embryos is limited to case reports (8)(9)(10)(11)(12)(13)(14)(15)(16); therefore, we retrospectively analyzed our clinical data on refrozen-thawed ETs, including perinatal outcomes of children born after embryo re-cryopreservation, to evaluate the safety of the refreezing procedure.…”