In vitro oogenesis, as yet, is not a viable technology. This is because the complexity involve in the process of making oocytes or embryos.

The OPU-IVP in cattle has been developed producing more than a million embryos annually. However the pregnancy rates with fresh embryos still are 10%, and with frozen 20% below the MOET’s ones, with a lot of variability, abortion and distocia caused by LPS and LOS. As practitioners we are using simultaneously both technologies. We hope the reaearchers will find protocols for in vivo oocyte capacitation, new culture systems (IVM,IVF and IVC) to produce metabolic normal embryos and improve DT freezing to solve these troubles.

An human ovum or oocycte is a reproductive haploid cell called a gamete that contains only 23 chromosomes from the woman.

After fertilization (aka egg activation) the human fertilized egg/human activated egg is a living human organism embryo with 46 chromosomes. The earliest single cell embryo - the pronuclear embryo - is called an ootid. The fertilized egg's outer membrane has instantly hardened to protect itself from polyspermy and after 24 hours the ootids two pronuclei have been fused into a single nucleus. At this point the single cell ootid is called a zygote. The zygote then proceeds to develop and divide and becomes known as a morula and later a blastocyst. Every human being starts life as single cell embryo. Eggs and sperm are not embryos.

An embryo that was frozen for 27 years was born in October of 2020. Her name is Molly Gibson. Her older sister, Emma, was frozen for 24 years. The two sisters were adopted as frozen embryos by their adoptive parents Tina and Ben Gibson who were just 26 years old when they adopted a batch of leftover frozen embryos.

Here is a link to the New York Times article:

https://www.nytimes.com/2020/12/03/science/tennessee-embryo-donate.html

There are approximately 1 million "leftover" frozen human embryos who should transferred to the womb of the genetic mother, or they should be allowed to be adopted and transferred to the womb of the adoptive mother. Sadly, the majority of frozen embryos - more than 50% - do not survive the freezing and thawing process, and only about one in three of the embryos will be able to implant itself after transferal to the maternal womb.

Crypreservation of embryos was banned in Germany in 1990 because it harms and kills human embryos, and it has also be banned in Italy and other countries for the same reason. Italy actively promotes the transfer of all frozen embryos, either to the genetic/biological mother or to an adoption mother.

The Nuremburg Code of Ethics prohibits non-therapeutic experimentation on human beings without their free and informed consent. This is why Germany passed its Embryo Protection Law that protects human embryos from harm.

Here is a link to this Law proposed in 1990 and passed in 1991:

https://www.google.com/search?q=Germany+Embryo+Proctection+Law+in+English&oq=Germany+Embryo+Proctection+Law+in+English+&aqs=chrome..69i57.18736j0j7&sourceid=chrome&ie=UTF-8

Elizabeth Rex Sullip Kumar Majhi C. J. Munar Thank you very much for your valuable inputs and opinions

The OPU-IVP in cattle has been developed producing more than a million embryos annually. However the pregnancy rates with fresh embryos still are 10%, and with frozen 20% below the MOET’s ones, with a lot of variability, abortion and distocia caused by LPS and LOS. As practitioners we are using simultaneously both technologies. We hope the reaearchers will find protocols for in vivo oocyte capacitation, new culture systems (IVM,IVF and IVC) to produce metabolic normal embryos and improve DT freezing to solve these troubles.

The OPU-IVP in cattle has been developed producing more than a million embryos annually. However the pregnancy rates with fresh embryos still are 10%, and with frozen 20% below the MOET’s ones, with a lot of variability, abortion and distocia caused by LPS and LOS. As practitioners we are using simultaneously both technologies. We hope the reaearchers will find protocols for in vivo oocyte capacitation, new culture systems (IVM,IVF and IVC) to produce metabolic normal embryos and improve DT freezing to solve these troubles.