PETALING JAYA: A young married couple who were desperately trying to get pregnant for four years were surprised to find out the reason behind their inability to conceive - they had been having sex the wrong way.

The 26-year-old man and his 24-year-old wife from China, whose identity were kept secret, consulted obstetrician Dr Liu Hongmei early this year, Chinese portal Guiyang Evening Post reported.

When asked about the wife's medical history, the couple told Dr Liu that they had been having sexual intercourse frequently.

The wife said sex had been incredibly painful for her, but she endured it in hopes of conceiving.

Dr Liu initially believed the wife could have a gynecological condition, but upon examining her, she discovered the woman was still a virgin.

The doctor then examined the woman's anus and identified the reason for their failure to conceive - they had been having anal intercourse for four years.

"The couple are very young. The man is 26 and the woman is 24. They are very healthy, but even though they have been married for four years they could not get pregnant," Dr Liu said.

"Because of that their family gave them a lot of pressure," she added.

Dr Liu then reportedly gave the couple a sex education handbook and "guidelines" before allowing them to go home.

The doctor's advice proved fruitful – the wife became pregnant a few months later.

They delivered the good news to Dr Liu by sending 100 eggs and a live chicken to her hospital as a gift.