Transferring one embryo rather than multiple embryos can help some infertile women over 35 years old conceive and give birth, according to a new study by Stanford University researchers published in the journal Fertility and Sterility. This study gives hope to older infertile women interested in IVF (in vitro fertilization), but don’t want twins or multiple births.
Single Blastocyst Transfer Study’s Success Rates
50 percent of the women in this study became pregnant after the single blastocyst transfer procedure, a success rate that is almost twice the national average for IVF women in this age group who use IVF. However, researcher Dr. Amin A. Milki, MD notes that the women in this study were carefully selected and are not representative of the wider population. Most women in this age do not have enough high-quality eggs to allow the transfer of only one embryo.
But for those who do, the single blastocyst transfer procedure offers a very good chance at pregnancy with a low chance of giving birth to twins.
This study’s findings may lead to a revision of ASRM (American Society for Reproductive Medicine) guidelines for women 35 or older, which currently recommends multiple embro transfers, one reason why women who undergo fertility treatments have a higher chance of having twins.
Currently, the ASRM recommends transferring two to three embryos for women between the ages of 35 and 37 and three to four embryos in women between the ages of 38 and 40.