Legal loopholes are allowing surrogacy agencies in China to cash in on the underground womb-to-rent business, sparking debates on ethics among the public.

Underground networks of surrogacy agents, hospitals, and doctors have sprung up in recent years as infertile Chinese couples with money hire surrogate mothers to have babies for them.

"We know it's not legal but it's worth the risk as my husband and I really want a baby to complete the family," said a 36-year-old woman surnamed Fang in Shenzhen, whose attempts to conceive never succeeded.