Men may contribute far more to a successful pregnancy than just sperm, with evidence suggesting seminal fluid primes a woman’s immune system to be more receptive to the foetus.
Researchers from the University of Adelaide have found a mechanism that may explain why women who have repeated exposure to their partner’s seminal fluid in the three to six months before conception have a much lower likelihood of pregnancy complications such as pre-eclampsia and foetal growth restriction.
The team’s findings were presented this week at the Australian Health and Medical Research Congress in Adelaide.
“The male makes a contribution that we hadn’t appreciated – it’s not just that one thing of sperm that’s important,” says Professor Sarah Robertson, co-director of the University of Adelaide’s Research Centre for Reproductive Health.
A study in mice has revealed that more frequent exposure to seminal fluid increases levels of a type of immune cell called a regulatory T cell, which has already been shown to play a key role in helping the mother’s immune system tolerate the foetus.
Early research in humans suggests the same mechanism may explain why women who conceive after less than three months of sexual cohabitation with the father-to-be have a significant increase in the risk of pre-eclampsia.
“We see it in pregnancies where people conceive very early in the relationship or after a one-night stand, but we also see it where people have used barrier methods of contraception and then immediately become pregnant after stopping using condoms,” says Robertson. Read more here.