Your egg might prefer some men’s sperm over others.
Microscopic mate choice
“Follicular fluid from one female was better at attracting sperm from one male, while follicular fluid from another female was better at attracting sperm from a different male,” said Professor Fitzpatrick.
“This shows that interactions between human eggs and sperm depend on the specific identity of the women and men involved.”
The egg might have its own preference in type of sperm and it is exercised by follicular fluid. The egg might attract more sperm from a certain male and not always the partner. So is the egg the decision maker in fertilization or the sperm? We have always thought that the sperm swims towards the egg and therefore is the one choosing the egg. The egg basically is a passive participant, waiting for the sperm. However recent research shows there may more than meet the eye.
Perhaps it makes sense since the egg has to risk it all, get one sperm, implant and become a human, whereas the sperm are in millions, anyone of them wins, the male wins. To find out more about mating and reproductive behaviors and opportunities, read up more on Professor John Fitzpatrick’s research on reproductive behaviors, opportunities and trade offs (https://www.su.se/english/profiles/jfrit-1.253654).
“The idea that eggs are choosing sperm is really novel in human fertility,” said Professor Daniel Brison, the Scientific Director of the Department of Reproductive Medicine at Saint Marys’ Hospital, which is part of MFT, and the senior author of this study.
The University of Manchester Honorary Professor added: “Research on the way eggs and sperm interact will advance fertility treatments and may eventually help us understand some of the currently ‘unexplained’ causes of infertility in couples.”
“I’d like to thank every person who took part in this study and contributed to these findings, which may benefit couples struggling with infertility in future.”
The article Chemical signals from eggs facilitate cryptic female choice in humans is published in the scientific journal Proceedings of the Royal Society B.
https://royalsocietypublishing.org/doi/10.1098/rspb.2020.0805
Research was supported by the Manchester University NHS Foundation Trust, the University of Manchester, the National Institutes of Health Research, a Knut and Alice Wallenberg Academy Fellowship, and a Wenner Gren Fellowship.