A University of Adelaide study released on Wednesday recommended regular sex between three and six months among couples for a healthier pregnancy. The basis of such findings is the releases during intercourse seminal fluids, besides sperm, which are needed to get the couple's immune system to respond correctly and lessen chances of pregnancy complications.
For some couples, the process could take up to 12 months, although the researchers said pregnancy also occurs as a result of a one-night stand. However, chances or rejection and miscarriage are greater as well as pregnancy complications such as pre-eclampsia.
"It's not so much about the likelihood of getting pregnant. It's more about health progression of pregnancy," Adelaide.now quoted Professor Sarah Robertson from the University of Adelaide who authored the study.
The study said seminal fluid elicits an inflammation-like response in a woman's cervix, which could be crucial for successful pregnancies. Besides millions of sperm, seminal fluid contains a complex mixture of free proteins and other molecules which play a critical role in creating a conducive environment for the female body to accept a pregnancy.
The study could benefit women who have problems becoming pregnant.
"The mechanisms that create immune receptiveness for pregnancy could be somehow lacking in couples susceptible to pregnancy failures," Ms Robertson explained.
The researchers studied a group of women who refrained from sex for at least 36 hours before a small sample of cervical tissue was collected. Another sample was collected 12 hours after sexual intercourse.
To enable the scientists to analyse the effect of seminal fluid on the number of immune cells and the expression of key immune system genes, they had the samples frozen.
Samples from the 12-hour period after coitus showed that the cervix had a reaction typically seen only during inflammation, while immune cells are activated to initiate and maintain immune responses which flood the cervix.
The findings, which help shatter myths about sex and pregnancy, were presented by the researchers 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," Ms Robertson added.