London: Researchers have found that surrogacy or `wombs for hire` from foreign surrogate mothers has increased in the past five years, particularly by Indian agencies.
The research, published in The Journal of Social Welfare and Family Law, reveals there is an increasing demand in the number of couples registering children to foreign surrogates.
"Parental orders" were granted following surrogacy to transfer the child from the surrogate mother to the commissioning parents, The Independent reported.
This process, driven particularly by Indian agencies, has risen from 47 times in 2007 and 133 in 2011, the study said.
But the real figures are believed to be much higher, and experts have warned of the increasing exploitation of women living in poverty who undergo the pregnancies to raise money.
According to the study, women rent their wombs for about USD 16,000 to USD 32,000.
Commercial surrogacy is permitted in the US and in many other countries including India, where it was legalised in 2002.
But it is banned in Britain and only expenses may be paid making it difficult for UK couples where neither partner is able to bear children to find women prepared to volunteer for the role.
"We have clinicians in this country who have links with overseas clinics. That was stopped with international adoption years ago. I don`t think the Human Fertilisation and Embryology Authority has been strong enough on this," Marilyn Crawshaw, author of the research and senior lecturer at the University of York, said.
"There is concern about child trafficking. The World Health Organisation held a meeting on this. Parents desperate to have children will pay thousands of pounds to foreign agencies to arrange the birth of their child.
Natalie Gamble, a lawyer specialising in surrogacy cases, said important regulations were in place to protect children at risk from international trafficking, but there were no safeguards in place for overseas surrogacy.
The practise follows a decline in international adoptions, which has plummeted to its lowest point in 15 years.