That's according to the first systematic review comparing IVF outcomes for people using their own eggs to those for people using a partner's. This research showed higher live birth rates but a greater risk of complications for those using reciprocal IVF.
The simulation made it possible to appreciate how a human embryo does not merely adhere to the uterine lining, but actively inserts itself. "We observe that the embryo pulls on the uterine matrix, moving and reorganizing it," explained Amélie Godeau, coauthor of the research, which was published in Science Advances. These movements could explain the pain some women report days after fertilization.