19/08/2014 12:47 BST | Updated 20/05/2015 06:12 BST

Australian Parents Of Thai Baby With Down's Syndrome Deny Abandoning Him

Pattaramon Chanbua, 21, poses with her baby boy Gammy at a hospital in Chonburi province, southeastern Thailand Sunday, Aug. 3, 2014. The Australian government is consulting Thai authorities after news emerged that Gammy, a baby with Downs Syndrome was abandoned with Chanbua, his surrogate mother, in Thailand by his Australian parents, according to local media. (AP Photo/Apichart Weerawong)

The parents of baby Gammy, who were reported to have abandoned their son after he was born with Down's Syndrome to a Thai surrogate mother, have insisted they didn't even know of his existence. The couple say they were told of the birth of only one child, Gammy's twin sister.

The Australian biological father of twins born to a Thai surrogate is reported to have told local TV news that the clinic's doctor only told them about the boy's sister.

A lawyer acting for the Australian parents, who are in their 50s, is expected to give a press conference detailing their side of the controversial story later today (Monday).

The surrogate herself, 21-year-old Pattaramon Janbua, claims she wasn't informed of the boy's condition until late in her pregnancy.

She said her doctors, the surrogacy agency and the baby's parents knew Gammy would be born with Down's Syndrome when she was four months pregnant but didn't tell her until the seventh month when the agency asked her - at the parents' request - to abort the disabled foetus.

Pattaramon said she refused the abortion on religious grounds and continued with the pregnancy of both Gammy, now six months old, and his twin sister.

The parents, who haven't been identified, took only the girl back with them to Australia.

Gammy now needs surgery for a congenital heart condition, according to media reports.

An online campaign in Australia had raised nearly £110,000 in donations so far for the operation.

Pattaramon said: "I want to warn those who are considering becoming a surrogate mother, don't only think about the money.

"If the child is born with an unusual condition or if anything goes wrong, it will become a burden for you and society."

The case has caused controversy in both Thailand and Australia and brought calls for commercial surrogacy to be banned in the Southeast Asian country.

Thailand is a top destination for medical tourism and many couples come for services such as fertility treatment and some for surrogacy.

Australian Prime Minister Tony Abbott said on Saturday that authorities there would look to see if there was anything they could do about the case.

He said: "It is an incredibly sad story."

Pattaramon said she agreed to a fee of 350,000 Thai baht (£6,500) to carry the twins for the couple.

She said they agreed to pay her another 150,000 baht (£2,700) to keep Gammy.

She wouldn't identify the agency or give details of the providers of medical services to her during the pregnancy.

Gammy is being treated for a lung infection in a hospital east of Bangkok and his condition is stable, a spokesman at the hospital said yesterday.

There are no laws governing surrogacy in Thailand. A law has been drafted but not yet submitted to parliament.

Story Of Baby With Down Syndrome Shows Surrogacy's Pitfalls

More on Parentdish: I am not Down's Syndrome, I am Mara