[In Depth] Can flu shots help women get pregnant?
Two new clinical trials are testing whether flu vaccines increase the effectiveness of in vitro fertilization (IVF). The studies draw on new discoveries about the immune system's role in reproduction. Doctors used to think that the immune system had to shut down during pregnancy so that it wouldn't destroy the embryo. Now, researchers realize that the immune system remains active but learns to accept the embryo, developing what's known as tolerance. The trials will test whether flu shots increase tolerance toward the embryo and improve the success rate of IVF. One trial includes women undergoing IVF with embryos created from their own eggs, and the other trial includes women who receive embryos created from donor eggs. Author: Mitch Leslie