This is one of a series of news items from abstracts of studies presented at the Annual Meeting of the American Society for Reproductive Medicine as complied by Dr. David Meldrum, Scientific Director of Reproductive Partners. We appreciate the enormous amount of work it takes to compile and comment on these abstracts.
One of the most common questions I hear when women miscarry is, "Why did this happen." Conventional wisdom is that is is usually caused by some abnormality in the chromosomes of the embryo. Now a study reported at ASRM in patients with recurrent pregnancy loss confirms that point of view.
In 177 cycles of couples with recurrent pregnancy loss, preimplantation genetic screening (PGS) using CGH was done by day 3 (143 cycles) or day 5 (34 cycles) biopsy. 63% of embryos were abnormal. But by transferring only chromosomally normal embryos he miscarriage rate was only 6% in this high risk group compared to an expected rate of 35%. This study confirms that idiopathic recurrent pregnancy loss is mostly caused by chromosome abnormalities, and that the chance of fetal loss is dramatically decreased using PGD. using only day 5 biopsy would be expected to produce even more reliable results without influencing the chance of success (although here 40% had ongoing pregnancies). Also, the ability to do an elective single embryo transfer (eSET) is a further benefit of CGH, not only for women under age 35.