Wednesday 11 July 2007
High IVF twin pregnancy clue
Source: European Society of Human Reproduction & Embryology 23rd annual meeting; Lyon, France: 1-4 July 2007
Examining reasons underling the high rate of twin pregnancies with IVF.
MedWire News: Time-lapse photography of blastocyst formation may have revealed clues behind the high rate of twin pregnancies resulting from IVF.
Dianna Payne (Mio Fertility Clinic, Yonago, Japan) and colleagues created a free-running film of 33 surplus frozen-thawed embryos using single images taken every 2 minutes from a digital camera attached to a microscope.
Overall, 26 embryos developed to the blastocyst stage and the blastocoele collapsed at least once in 25 of these, the team reported at the European Society of Human Reproduction and Embryology 23rd annual meeting in Lyon, France.
Fifteen embryos degenerated in culture, and 11 did not re-expand after collapse and subsequently degenerated.
Two of the 26 embryos, and possibly a third, had two distinct inner cell masses (ICMs), which appeared to result from some ICM cells relocating during an early collapse.
“Our findings that collapse was associated with degeneration of blastocysts as well as the formation of the second ICM suggest that these episodes in which blastocoele volume cannot be maintained may be an artefact of culture,” said Payne.
“Furthermore, our findings suggest that the formation of two ICMs during blastocyst development may be the cause of the high monozygotic rate after extended culture.”
Posted: 06 July 2007
http://www.orgyn.com/en/news/2007/We...win_pregna.asp
High IVF twin pregnancy clue 
