CHOOSING a partner for marriage is a time-consuming social endeavor but after marriage the “compatability check” still continues on the conjugal bed – where human eggs become selective in sperm preference.
This means – the traditional understanding that each living person is a “champion” because he or she is the outcome [ihc-hide-content ihc_mb_type=”show” ihc_mb_who=”2,3,5″ ihc_mb_template=”1″ ] of the lone sperm which successfully managed to reach the egg during connubial liaisons no longer holds water!
This is according to a finding by the Stockholm University and Manchester University NHS Foundation Trust which showed that eggs issue chemical signals to choose sperm of their preference.
Simply put – different women’s eggs attract different men’s sperm not necessarily their partner’s!
“Human eggs release chemicals called chemoattractants that attract sperm to unfertilized eggs. We wanted to know if eggs use these chemical signals to pick which sperm they attract,” says John Fitzpatrick, an Associate Professor at Stockholm University.
According to him, the researchers examined how sperm respond to follicular fluid, which surrounds eggs and contains sperm chemoattractants. The researchers attempted to find out if follicular fluids from different females attracted sperm from some males more than others.
Microscopic match-making
“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,” says Fitzpatrick.
“This shows that interactions between human eggs and sperm depend on the specific identity of the women and men involved.”
He says, the egg does not always agree with the women’s choice of partner.
“The researchers found that eggs did not always attract more sperm from their partner compared to sperm from another male,” he adds.
So, is this the egg’s or sperm’s choice?
Fitzpatrick explained that the sperm has only one task at hand, to fertilize eggs—so it doesn’t make sense for them to be choosy.
“Eggs on the other hand can benefit by picking high quality or genetically compatible sperm.
“The idea that eggs are choosing sperm is really novel in human fertility,” says 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.” [/ihc-hide-content]
