ANAND, India - Every night in this quiet western Indian city, 15 pregnant women prepare for sleep in the spacious house they share, ascending the stairs in a procession of ballooned bellies.

A team of maids, cooks and doctors looks after the women. The young mothers of Anand, a place famous for its milk, are pregnant with the children of infertile couples from around the world.

The small clinic at Kaival Hospital matches infertile couples with local women, cares for the women during pregnancy and delivery, and counsels them afterward. Anand's surrogate mothers, pioneers in the growing field of outsourced pregnancies, have given birth to about 40 babies.

More than 50 women in this city are now pregnant with the children of couples from the United States, Taiwan, Britain and beyond. The women earn more than many would make in 15 years. But the program raises a host of uncomfortable questions that touch on morals and modern science, exploitation and globalization, and that most natural of desires: to have a family.

Nayna Patel, the physician behind Anand's baby boom, defends her work as meaningful for everyone involved.

"There is this one woman who desperately needs a baby and cannot have her own child without the help of a surrogate. And at the other end there is this woman who badly wants to help her [own] family," Patel said. "If this female wants to help the other one . . . why not allow that?"

Experts say commercial surrogacy - what has been called "wombs for rent" - is growing in India. While no reliable numbers track such pregnancies nationwide, doctors work with surrogates in virtually every major city. The women are impregnated with embryos made in lab dishes using the egg and sperm of couples unable to conceive on their own.

Commercial surrogacy has been legal in India since 2002, as it is in many other countries, including the United States. But India is the leader in making it a viable industry rather than a rare fertility treatment for the same reasons outsourcing in other industries has been successful: a wide labor pool working for relatively low rates.

Critics say the couples are exploiting poor women in India - a country with an alarmingly high maternal death rate - by hiring them at a cut-rate cost to undergo the hardship, pain and risks of labor.

"It raises the factor of baby farms in developing countries," said John Lantos of the Center for Practical Bioethics in Kansas City, Mo. "It comes down to questions of voluntariness and risk."

Ritu Sodhi, a furniture importer from Los Angeles who was born in India, spent $200,000 trying to get pregnant through in-vitro fertilization, and was considering spending $80,000 more to hire a surrogate mother in the United States.

Then, on the Internet, Sodhi found Patel's clinic. After spending about $20,000 - more than many couples because it took the surrogate mother several cycles to conceive - Sodhi and her husband are now back home with their 4-month-old baby, Neel.

Young women are flocking to Patel's clinic. Suman Dodia, a pregnant, baby-faced 26-year-old, said she will buy a house with the $4,500 she receives from the British couple whose child she's carrying. It would have taken her 15 years to earn that on her maid's monthly salary of $25.

Dodia's own three children were delivered at home and she said she never visited a doctor during those pregnancies.

"It's very different with medicine," Dodia said, resting her hands on her hugely pregnant belly. "I'm being more careful now than I was with my own pregnancy."

Patel said she carefully chooses which couples to help and which women to hire as surrogates. She accepts only couples with serious fertility issues, like survivors of uterine cancer. The surrogate mothers have to be between 18 and 45, have at least one child of their own, and be in good medical shape.

Like some fertility reality show, a rotating cast of surrogate mothers live together in a home rented by the clinic and overseen by a former surrogate mother. They receive their children and husbands as visitors during the day, when they're not busy with English or computer classes.

The industry is not regulated by the government, but health officials have issued nonbinding ethical guidelines and called for legislation to protect the surrogates and the children.

The surrogate mothers and the parents sign a contract that promises the couple will cover all medical expenses in addition to the woman's payment, and the surrogate mother will hand over the baby after birth. The couples fly to Anand for the in-vitro fertilization and again for the birth. Most couples end up paying the clinic less than $10,000 for the entire procedure, including fertilization, the fee to the mother and medical expenses.

Counseling is a major part of the process, and Patel tells the women to think of the pregnancy as "someone's child comes to stay at your place for nine months."

"The fetus is theirs, so I'm not sad to give it back," said Kaila Gheewala, 25, who plans to save the $6,250 she's earning for her two daughters' education. Patel said none of the surrogate mothers has had especially difficult births or serious medical problems, but risks are inescapable.

"We have to be very careful," she said. "We overdo all the health investigations. We do not take any chances."