Page URL:

Scientists discover why regular sex prior to conception reduces pregnancy complications

3 December 2012
Appeared in BioNews 684

A man may contribute more than just sperm to the process of conception, research suggests.

Presenting the work at a conference, Professor Sarah Robertson from the University of Adelaide in Australia confirmed that repeated exposure to a partner's seminal fluid before conception leads to a lower chance of complications, including miscarriage and pre-eclampsia, during early pregnancy.

'We now know that an average of at least three to six months coitus with their partner is necessary to get their immune system to respond correctly to enable a healthy pregnancy', said Professor Robertson.

Professor Robertson further compared the implications of pregnancy on the immune system of the mother with those arising from an organ transplant, saying pregnancy involved 'foreign tissue living in a female body for nine months and so you have to have transplantation tolerance or immune tolerance to allow that to occur'.

Sex prior to conception is thought to expose the female immune system to the immunological signature of her partner and thus help establish that immune tolerance.

But just how the exposure to the partner's seminal fluid does this is unclear. Research done in Professor Robertson's lab suggests that small RNA molecules, called micro RNA, in semen may interact with cells in the female reproductive tract. At this point, Professor Robertson says, the micro RNA can alter gene expression and modify tissue function to bring about the immune changes.

The work may have implications for research into currently unexplained problems in early pregnancy. The abstract for Professor Robertson's talk at the conference suggests that 'pathologies of pregnancy such as implantation failure or recurrent miscarriage may be due to inadequate male-female seminal fluid communication, or over-zealous female quality control'.

Professor Robertson stressed that, when it came to pre-conception sex, 'it's not so much about the likelihood of getting pregnant, it's more about health progression of pregnancy'.

Couples should practice sex for three to six months before conception for a healthier baby
Adelaide Now |  27 November 2012
Home Page
The Australian Health and Medical Research Congress |  27 October 2021
Men contribute more than sperm to pregnancy
ABC News |  27 November 2012
Practice really does make perfect: Why having regular sex increases your chance of having a healthy baby
Mail Online |  27 November 2012
Seminal fluid, not just sperm, enables pregnancy
Cosmos |  28 November 2012
19 June 2017 - by Cara Foley 
The fetal immune system is more mature in the second trimester than previously thought, which could assist research into diseases, miscarriage and immune tolerance, researchers say...
18 June 2012 - by Helen Brooks 
An unhealthy lifestyle may not affect sperm quality as much as previously thought. A study in the journal Human Reproduction indicates that smoking, high alcohol consumption and being overweight all have little effect on semen quality...
11 June 2012 - by Dr Maria Teresa Esposito 
Immune rejection, the body's defence mechanism, triggered in response to foreign tissues, is a huge problem for transplant operations. But why does a mother's immune system not reject the developing fetus? The answer may lie in modifications to genes that usually activate part of the immune response, according to scientists...
28 May 2012 - by Edwin Davies 
The fluidity of semen is an idea that Lisa Jean Moore returns to throughout her book 'Sperm Counts: Overcome by Man's Most Precious Fluid', though she is often less concerned with the physical qualities of the substance than she is with its fluidity as a concept...
20 September 2010 - by Dr Charlotte Maden 
Scientists claim to have developed a new technique for sperm preservation, which allows more functioning sperm to be recovered. The Chilean and German team reportedly used vitrification, which is currently used for cryopreserving ('freezing') eggs and embryos, to successfully preserve sperm...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.