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New Methods of In Vitro Fertilization

Expanding group gamete intrafallopian fetal transfer, zygote intrafallopian fetal transfer, infertility, artificial insemination of highly technological methods for achieving pregnancies.

This has permitted many couples who in the past would not have had this option to achieve pregnancies.

The speed with which these technologies have been expanding has made it difficult for physicians to keep abreast of what is happening and what is appropriate

This presentation will attempt to provide physicians with what is available today.

ARTs involve many variations of the same theme

Terms related to ARTs

In vitro fertilization VF)

Gamete intrafallopian transfer (GIFT)

Pronuclear intrafallopian transfer (PROST)

Zygote intrafallopian transfer (ZIFT)

Garnetes: sperm and oocytes (eggs)

Zygote: fertilized oocyte

Embryo: any fertilized oocyte, but prior to 14 day, sometimes referred to as "preembryo"

The meaning of these terms is best understood by reviewing the normal sequence of events from ovalaxion through division

Once fertilization has taken place, the genetic material from both parents form visible circles within the oocyte's cytoplasm that are called pronuclei

This precedes the alignment of genetic material and the first cell division

These fertilized oocytes with visible pronuclei are called pronuclear embryos

The disappearance of the pronuclei signals that chromosomal alignment has begun; this is termed syngamy

The pronuclei become visible somewhere around 16 hours after the oocytes are inseminated

The first cell division occurs about 24 hours after insemination and further cell divisions occur about every 12 hours

3. Any fertilized oocyte is technically an embryo but prior to 14 days they are sometimes referred to as preembryos; fertilized oocytes are also known as "zygotes"

Thus, to return to the variations of ART

IVF involves

Oocyte retrieval

Extracorporeal fertilization