Biomaterial Database

Fertilization in vitro and development to term of unfertilized mouse oocytes previously stored at --196 degrees C. 1977

D G Whittingham

Unfertilized mouse oocytes were frozen and stored at --196 degrees C. Immediately after thawing 331 out of 463 MF1 oocytes (71-5%) and 271 out of 410 F1 (C57BL X CBA) hybrid oocytes (66-1%) were morphologically normal. No significant difference was found between the survival of oocytes frozen and thawed with (70%) or without (66%) the surrounding cumulus cells. Fertilization in vitro of frozen-thawed oocytes was significantly lower than that of freshly collected control oocytes. The overall fertilization rate in vitro for MF1 oocytes was lower than with F1 (C57BL X CBA) hybrid oocytes. The presence or absence of cumulus cells during fertilization in vitro did not affect the fertilization rate. Live 14-day fetuses were obtained after transfer of frozen-thawed unfertilized oocytes directly to the oviducts of females mated with fertile males. However, much higher rates of survival (up to 45%) to 14-day fetuses and live-born were found after the fertilization of frozen-thawed oocytes in vitro and subsequent transfer at the 2-cell or blastocyst stage to pseudopregnant recipients.

UI	MeSH Term	Description	Entries
D009865	Oocytes	Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).	Ovocytes,Oocyte,Ovocyte
D010063	Ovum	A mature haploid female germ cell extruded from the OVARY at OVULATION.	Egg,Egg, Unfertilized,Ova,Eggs, Unfertilized,Unfertilized Egg,Unfertilized Eggs
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell
D004624	Embryo Transfer	The transfer of mammalian embryos from an in vivo or in vitro environment to a suitable host to improve pregnancy or gestational outcome in human or animal. In human fertility treatment programs, preimplantation embryos ranging from the 4-cell stage to the blastocyst stage are transferred to the uterine cavity between 3-5 days after FERTILIZATION IN VITRO.	Blastocyst Transfer,Tubal Embryo Transfer,Tubal Embryo Stage Transfer,Embryo Transfers,Transfer, Embryo,Transfers, Embryo
D005260	Female		Females
D005306	Fertilization	The fusion of a spermatozoon (SPERMATOZOA) with an OVUM thus resulting in the formation of a ZYGOTE.	Conception,Fertilization, Delayed,Fertilization, Polyspermic,Conceptions,Delayed Fertilization,Delayed Fertilizations,Fertilizations,Fertilizations, Delayed,Fertilizations, Polyspermic,Polyspermic Fertilization,Polyspermic Fertilizations
D005615	Freezing	Liquids transforming into solids by the removal of heat.	Melting
D006824	Hybridization, Genetic	The genetic process of crossbreeding between genetically dissimilar parents to produce a hybrid.	Crossbreeding,Hybridization, Intraspecies,Crossbreedings,Genetic Hybridization,Genetic Hybridizations,Hybridizations, Genetic,Hybridizations, Intraspecies,Intraspecies Hybridization,Intraspecies Hybridizations
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia