A research team supervised by Universite Laval scientist Marc-Andre Sirard has identified genetic markers that allow the selection of eggs with the best chance of leading to successful pregnancy after in vitro fertilization (IVF).
This finding could both increase the success rate of single embryo transfer and diminish the risk of multiple pregnancies. The details of the method developed by the researchers, for which an international patent application has been filed, are explained on the website of the scientific journal Human Reproduction.
Eggs recovered in the course of the IVF process are surrounded by follicular cells that are removed before the actual fertilization procedure begins. “While in the ovaries, these cells and the eggs are in very close interaction,” explains Sirard. “A first experiment we conducted on bovine follicular cells led us to believe that these cells might possess specific markers that would be able to give us information about the quality of an egg.”
With the help of 40 women recruited in a fertility clinic, researchers compared follicular cells surrounding eggs that ultimately led to successful pregnancies—i.e. “good” eggs—to cells surrounding ovules that did not result in pregnancy. This comparison led to the identification of five genes expressed more abundantly in follicular cells surrounding good eggs.