In a Cambodian hospital, a group of terrified new mothers nurse tiny babies under the watch of police guards. They're surrogates, desperately poor women promised $10,000 to bear children for parents in China. But they were arrested under new anti-trafficking rules, and now they face an agonising choice: either they agree to keep children they didn't want and can't easily afford to bring up, children who aren't genetically theirs - or they honour their surrogacy contracts, and face up to 20 years in jail. Tim Whewell reports on the suffering as country after country in Asia cracks down on commercial surrogacy - and asks whether the detained mothers are criminals - or victims.