TY - JOUR
T1 - Three years of routine vitrification of human zygotes: Is it still fair to advocate slow-rate freezing?
AU - Al-Hasani, Safaa
AU - Ozmen, Batuhan
AU - Koutlaki, Nikoleta
AU - Schoepper, Beate
AU - Diedrich, Klaus
AU - Schultze-Mosgau, Askan
PY - 2007/3
Y1 - 2007/3
N2 - Cryopreservation of human oocytes and embryos is a necessary tool in assisted reproduction treatment that leads to an increased cumulative outcome while decreasing costs. Vitrification is a cryopreservation technique that leads to a glass-like solidification, with rapid cooling of cells or tissues. Nowadays vitrification is claimed to be the future of cryopreservation of human embryos due to improved survival rates and clinical outcomes. This study was conducted at a university clinic to assess the safety and efficiency of vitrification of human zygotes as a routine procedure. A total of 849 pronuclear-stage (PN) zygotes were vitrified between March 2004 and July 2006. During this period, 103 cycles of cryopreserved embryo transfer were completed. In total, 339 PN zygotes were thawed resulting in an 89% survival rate (302 PN zygotes). The mean number of embryos per transfer was 2.2. The pregnancy rate obtained was three times higher (36.9%) than that obtained with the slow-rate freezing method (10.2%) used previously in the same centre. In conclusion, vitrification of human zygotes at the pronuclear stage seems to be a successful and reliable method with favourable outcomes and can be recommended as a routine technique for cryopreservation of human embryos.
AB - Cryopreservation of human oocytes and embryos is a necessary tool in assisted reproduction treatment that leads to an increased cumulative outcome while decreasing costs. Vitrification is a cryopreservation technique that leads to a glass-like solidification, with rapid cooling of cells or tissues. Nowadays vitrification is claimed to be the future of cryopreservation of human embryos due to improved survival rates and clinical outcomes. This study was conducted at a university clinic to assess the safety and efficiency of vitrification of human zygotes as a routine procedure. A total of 849 pronuclear-stage (PN) zygotes were vitrified between March 2004 and July 2006. During this period, 103 cycles of cryopreserved embryo transfer were completed. In total, 339 PN zygotes were thawed resulting in an 89% survival rate (302 PN zygotes). The mean number of embryos per transfer was 2.2. The pregnancy rate obtained was three times higher (36.9%) than that obtained with the slow-rate freezing method (10.2%) used previously in the same centre. In conclusion, vitrification of human zygotes at the pronuclear stage seems to be a successful and reliable method with favourable outcomes and can be recommended as a routine technique for cryopreservation of human embryos.
UR - http://www.scopus.com/inward/record.url?scp=33947495727&partnerID=8YFLogxK
U2 - 10.1016/S1472-6483(10)60869-3
DO - 10.1016/S1472-6483(10)60869-3
M3 - Journal articles
C2 - 17359578
AN - SCOPUS:33947495727
SN - 1472-6483
VL - 14
SP - 288
EP - 293
JO - Reproductive BioMedicine Online
JF - Reproductive BioMedicine Online
IS - 3
M1 - 2672
ER -