It may sound obvious but couples who want to have a baby should regularly have sex first, say scientists.
A study found women had a better chance of having a healthy baby if they had repeated exposure to their partner's sperm before they conceived. This was because it gave their immune systems time to build up a tolerance to the foreign fluid and so support a pregnancy.
Want to have a baby? You're more likely to have a healthy pregnancy if you've had some practice beforehand
Research author Prof Sarah Robertson from the University of Adelaide, said: '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.'
She added that this process could take up to a year for some couples.
While couples are able to get pregnant from a one-night stand, Prof Robertson said the chances of rejection and miscarriage are far greater as are pregnancy complications like pre-eclampsia.
CHANCES OF CONCEPTION
'It's not so much about the likelihood of getting pregnant, it's more about health progression of pregnancy,' she told adelaidenow.com.
'You're more likely to have a healthy pregnancy if you've had some practice beforehand.'
In the UK around one in six couples have difficulty conceiving. A couple will only be diagnosed as being infertile if they have not managed to have a baby after two years of trying.
Miscarriages are much more common than most people realise. Around one in eight pregnancies end in miscarriage where the woman knows she is pregnant - many more end before she realises she is pregnant.
It is thought that two thirds of early miscarriages are due to abnormal chromosomes in the babies.
Losing three or more pregnancies in a row is uncommon affecting around one per cent of women.
The latest fertility research will be presented by Prof Robertson at the Australian Society for Medical Research Congress in Adelaide.
Read more: http://www.dailymail.co.uk/health/article-2239104/Why-having-sex-increases-chance-having-healthy-baby.html#ixzz2DRsxtRUj
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