University of Adelaide Professor Sarah Robertson, who is leading the research, says tests discovered that females have an [...]]]> The age old male view that women are too picky has been taken to a whole new level after research found the female reproductive system may be rejecting sperm it doesn’t find good enough to create a pregnancy.

University of Adelaide Professor Sarah Robertson, who is leading the research, says tests discovered that females have an in-built quality control system, that assesses if the male partner is quality enough to invest her reproductive energy in.

“Part of this whole process is it’s a way of the female body evaluating whether the time is right and whether this particular partner is the right one to conceive a pregnancy with.

“Some women have higher thresholds to responding to this signalling pathway. It might be that with one partner they’re having more trouble than they might with another partner.

“What we understand is that there is a partner-specific component to this. Some combinations of men and women might not be compatible and it’s possible that the immune systems of some women aren’t responding correctly to their partner’s triggering molecules.

In the past, blame has generally been put with the woman if a couple is struggling to conceive and the man has healthy sperm.

But Professor Robertson says her findings show there may be another element to it and with further research there may be tests and treatments later down the track.

The research has primarily been on mice and pigs, but Professor Robertson says there is some indication that it will have the same or similar effect on human females.

“We’ve discovered that there are signalling molecules in the seminal fluid, so that after coitus when that fluid travels from the male to the female reproductive tissues it activates gene expression changes and also changes in the female immune system that increase the likelihood of a pregnancy occurring,” she said.

“At the moment we’ve done lots of work on mice and pigs and we’ve done a little bit of work with human cells and we’ve found if we put seminal fluid on cells in vitro that we get the same kind of changes in human cells.

Professor Robertson says this discovery could be extremely important from an evolutionary perspective, because it means the female body has the ability to decide when the time is right to fall pregnant.

The University of Adelaide research team is looking for female volunteers from 18-40 who have had a tubal ligation, but are in a stable, sexually active relationship.

Via: abc.net.au