Couples desperate for children are turning to India, where relaxed laws on surrogacy means the business of babies is booming.

In India, a womb can be rented for about $3,000 and in vitro fertilization treatment is a fraction of what it costs in the west.

"My criteria is very strict," Dr. Anup Gupta told Sky News. "The surrogate must be healthy and she must already have a family with at least one or two children of her own, minimum. She must not be doing this primarily for financial reasons but because she wants to help another family."

Gupta says he gets about 15 patients from abroad every month looking for a surrogate.

Most of the time he uses eggs and sperm harvested from the couple and then implants the embryo into the surrogate mother.

In return, the couple pays all of her medical expenses in addition to other lump sums.

By the time a baby is born, the woman who has effectively ‘rented’ out her womb stands to make around $7,000.

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