When was the first embryo transfer performed?
1399392#1
Embryo transfer can be done at day two or day three, or later in the blastocyst stage, which was first performed in 1984.
Embryo transfer
1399392#25
The first transfer of an embryo from one human to another resulting in pregnancy was reported in July 1983 and subsequently led to the announcement of the first human birth 3 February 1984. This procedure was performed at the Harbor UCLA Medical Center under the direction of Dr. John Buster and the University of California at Los Angeles School of Medicine.
Embryo transfer
28343289#11
The first ever pregnancy derived from a frozen human embryo was reported by Alan Trounson & Linda Mohr in 1983 (although the fetus aborted spontaneously at ten weeks of gestation); the first term pregnancy derived from a frozen embryo was born in 1984. Since then and up to 2008 it is estimated that between 350,000 and half a million IVF babies have been born from embryos frozen at a controlled rate and then stored in liquid nitrogen; additionally a few hundred births have been born from vitrified oocytes but firm figures are hard to come by. It may be noted that Subash Mukhopadyay from Kolkata, India reported the successful cryopreservation of an eight cell embryo, storing it for 53 days, thawing and replacing it into the mother’s womb, resulting in a successful and live birth as early as 1978- a full five years before Trounson and Mohr had done so. A small publication of Mukherjee in 1978 clearly shows that Mukherjee was on the right line of thinking much before anyone else had demonstrated the successful outcome of a pregnancy following the transfer of a 8-cell frozen-thawed embryo into human subjects transferring 8-cell cryopreserved embryos." (Current Science, Vol .72. No. 7, 10 April 1997)
Embryo cryopreservation
1399392#33
The development of various methods of cryopreservation of bovine embryos improved embryo transfer technique considerably efficient technology, no longer depending on the immediate readiness of suitable recipients. Pregnancy rates are just slightly less than those achieved with fresh embryos. Recently, the use of cryoprotectants such as ethylene glycol has permitted the direct transfer of bovine embryos. The world's first live crossbred bovine calf produced under tropical conditions by Direct Transfer (DT) of embryo frozen in ethylene glycol freeze media was born on 23 June 1996. Dr. Binoy Sebastian Vettical of Kerala Livestock Development Board Ltd has produced the embryo stored frozen in Ethylene Glycol freeze media by slow programmable freezing (SPF) technique and transferred directly to recipient cattle immediately after thawing the frozen straw in water for the birth of this calf. In a study, in vivo produced crossbred bovine embryos stored frozen in ethylene glycol freeze media were transferred directly to recipients under tropical conditions and achieved a pregnancy rate of 50 percent. In a survey of the North American embryo transfer industry, embryo transfer success rates from direct transfer of embryos were as good as to those achieved with glycerol. Moreover, in 2011, more than 95% of frozen-thawed embryos were transferred by Direct Transfer.
Embryo transfer
1510374#11
No one knows for sure when the first true embryo adoption occurred. The term was used as early as the mid-1980s, in the legal literature. Devroey et al., Dr. Maria Bustillo in Florida, and Dr. Howard Jones in Virginia have reported embryo transfers occurring between 1986 and 1990 that clearly represented adoption of remaining embryos.
Embryo donation
19043446#0
John Edmond Buster (born July 18, 1941) working at the University of California at Los Angeles School of Medicine, directed the research team that performed history's first embryo transfer from one woman to another resulting in a live birth. It was performed at the Harbor-UCLA Medical Center, reported in July 1983, and culminated in the announcement of the first human birth February 3, 1984. In the procedure, an embryo that was just beginning to develop was transferred from the woman in whom it had been conceived by artificial insemination to another woman who gave birth to the infant 38 weeks later. The sperm used in the artificial insemination came from the husband of the woman who bore the baby.
John Buster
1399392#9
Laboratories have developed grading methods to judge oocyte and embryo quality. In order to optimise pregnancy rates, there is significant evidence that a morphological scoring system is the best strategy for the selection of embryos. Since 2009 where the first time-lapse microscopy system for IVF was approved for clinical use, morphokinetic scoring systems has shown to improve to pregnancy rates further. However, when all different types of time-lapse embryo imaging devices, with or without morphokinetic scoring systems, are compared against conventional embryo assessment for IVF, there is insufficient evidence of a difference in live-birth, pregnancy, stillbirth or miscarriage to choose between them. A small prospectively randomized study in 2016 reported poorer embryo quality and more staff time in an automated time-lapse embryo imaging device compared to conventional embryology.
Embryo transfer
31525688#1
Embryo rescue was first documented in the 18th century when Charles Bonnet excised "Phaseolus" and "Fagopyrum" embryos and was successful in it , planted them in soil and the cross resulted in dwarf plants. Soon after this, scientists began placing the embryos in various nutrient media. During the period of 1890 to 1904, systems for embryo rescue became systematic by applying nutrient solutions that contained salts and sugars and applying aseptic technique. The first successful "in vitro" embryo culture was performed by Hanning in 1904, he however described problems with precocious embryos that resulted in small, weak, and often inviable plantlets.Depending on the organ cultured, it may be referred to as either embryo, ovule, or ovary culture. Ovule culture or in ovolo embryo culture is a modified technique of embryo rescue whereby embryos are cultured while still inside their ovules to prevent damaging them during the excision process. Ovary or pod culture, on the other hand employs the use of an entire ovary into culture. It becomes necessary to excise the entire small embryo to prevent early embryo abortion. However, it is technically difficult to isolate the tiny intact embryos, so often ovaries with young embryos, or entire fertilized ovules will be used.
Embryo rescue
28343289#4
Direct Frozen Embryo Transfer: Embryos can be frozen by SPF in ethylene glycol freeze media and transfer directly to recipients immediately after water thawing without laboratory thawing process. The world's first crossbred bovine embryo transfer calf under tropical conditions was produced by such technique on 23 June 1996 by Dr. Binoy S Vettical of Kerala Livestock Development Board, Mattupatti
Embryo cryopreservation
53827714#1
The first attempt to edit the human germline was reported in 2015, when a group of Chinese scientists used the gene editing technique CRISPR/Cas9 to edit single-celled, non-viable embryos to see the effectiveness of this technique. This attempt was rather unsuccessful; only a small fraction of the embryos successfully spliced the new genetic material and many of the embryos contained a large amount of random mutations. The non-viable embryos that were used contained an extra set of chromosomes, which may have been problematic. In 2016, another similar study was performed in China which also used non-viable embryos with extra sets of chromosomes. This study showed very similar results to the first; there were successful integrations of the desired gene, yet the majority of the attempts failed, or produced undesirable mutations.
Human germline engineering
1399392#5
Embryo transfer can be performed after various durations of embryo culture, conferring different stages in embryogenesis. The main stages at which embryo transfer is performed are cleavage stage (day 2 to 4 after co-incubation) or the blastocyst stage (day 5 or 6 after co-incubation).
Embryo transfer
1399392#6
Embryos who reach the day 3 cell stage can be tested for chromosomal or specific genetic defects prior to possible transfer by preimplantation genetic diagnosis (PGD). Transferring at the blastocyst stage confers a significant increase in live birth rate per transfer, but also confers a decreased number of embryos available for transfer and embryo cryopreservation, so the cumulative clinical pregnancy rates are increased with cleavage stage transfer. Transfer day 2 instead of day 3 after fertilization has no differences in live birth rate.
Embryo transfer