ANAND — Maanasi is ready. The 34-year-old is lying on the examination table, her feet in stirrups, waiting for Dr. Patel to arrive. Two nurse’s aides point a lamp at her belly. Maanasi barely lets out a sigh when the doctor implants two embryos inside of her, before leaving without a single word. The operation didn’t even last 10 minutes. The clients, an American couple, had sent six frozen embryos by plane. Another attempt will still be possible, should this one fail.

With her small sack on her shoulder, the young woman will be taken to the “house of surrogates,” a few hundred meters from the clinic, where she will be staying until the baby is born. That is also when Maanasi will meet the clients for the first time, just after the birth. She will then be able to go back home to her village, to her husband and her two children, aged seven and nine. And in her bank account, which will have been opened for the occasion, there will be $4,000 for her trouble.

How could she refuse such a deal, when she normally earns under a dollar a day? The nine months and labor amount to the equivalent of 20 years’ wages.

This is Anand, India, a medium-sized town with 150,000 inhabitants, located 100 kilometers from Ahmedabad, the largest city in the state of Gujarat, in the northwest of the country. Until recently, this typical town with its backfiring rickshaws, its noisy mess of street peddlers, its scrawny cows and stray dogs, was the milk capital of India.

Thanks to the success of the Akanksha Infertility Clinic, it is now the world’s hub for babies: 100 pregnant women here are carrying babies that are not theirs. Many of them are expecting twins. Indeed, to maximize the chances of success, two or even three embryos are often implanted, even if that means later having to proceed to an “embryonic reduction,” if that’s the clients’ wish. And because most of the future parents want to be present on the day of birth, the babies are often delivered through Caesarean section, which can be scheduled in advance.

While competitors are still trying to play catch-up, employing surrogate mothers here and there, Dr. Nayna Patel managed in 10 years to turn her clinic’s work into an almost industrial process.

On Aug. 5, her 500th surrogate mother, a 28-year-old woman whose husband left her with two small children, gave birth to a baby girl for a wealthy couple from the state of Uttar Pradesh, in the country’s north.

Indian people represent about a third of the clinic’s clients. The rest come from all over the world, from Belgium and Australia to Japan, Israel or Botswana. “Thirty-one countries in total,” Patel says. In 10 years, nearly 700 children were born from surrogate mothers in her clinic. And according to the statistics that she gathers with meticulous care, the clinic’s pace is gaining: three babies in 2006, 69 in 2008, and 147 in 2012.

The sector, estimated at several million dollars annually, shows every sign of thriving. It’s estimated that 600 children were born from surrogate mothers last year alone, and this is just the beginning. The reasons for this success are obvious: a global shortage of adoptable children, the rise of gay marriage (although Patel refuses to work with gay couples), and the increasing acceptance of surrogacy, which is now legal in about 15 countries. But most of them outlaw women being paid for it. As a result, the candidates are few.

But that’s not the case in the United States or in India, where this service has become a booming business, with dozens of agencies, intermediaries and specialized clinics. But while having a surrogate mother carrying a baby costs $100,000 in the U.S., it’s just a fraction of that price in India. Everything here is cheaper, from health costs and doctors to legal services, including of course the surrogate mothers. It costs about $30,000, extras not included, to effectively rent the uterus of an American woman, but only $4,000 or $5,000, all included, in India.

Is this progress?

“What is preventing the industry from growing even more is the lack of good surrogates and their price, which a lot of middle-class couples cannot afford,” explains John Weltman, head of Circle Surrogacy, a specialized agency in Boston.

With its 250 million poor people, India has a virtually unlimited pool of potential surrogate mothers. Only Thailand, which just entered the market with the promise of being 20% cheaper than India, can hope to compete. But Patel has a good head start. American agencies have already asked to work with her. She is suspicious, though, and prefers to keep control of the “production.” So she personally does most of the implants and deliveries. “But if I find a serious partner, why not?” she adds.

Is this the ultimate consequence of globalization? A disgraceful exploitation of women’s bodies? A commodification of children? To be sure, it is breathtakingly disturbing to imagine these babies being made to measure thanks to a simple Mastercard and the efficiency of an assembly line: sperm flakes and egg cells bought online, fertilized, frozen, then sent by plane to the four corners of the earth to be implanted in the bellies of these women kept like chickens.

And yet, Patel brushes these criticisms aside. “First of all, the patients can move around. We try whenever possible to work with fresh embryos because they give much better results. Then, at least one of the parents must have a biological link with the baby. People can buy either the sperm or the ovum, but not both. Finally, when an infertile couple has to resort to buying an ovum, they usually get it from a donor who looks like them, not from a model.”

With her regular features and her discreet pearl necklace, this dynamic self-assured woman of 53 defends her small company tooth and nail. All it does, she claims, is try to “make people happy.”

“We help to lift women out of their misery while at the same time offering others the happiness of being a mother. The instinct of procreation and that of survival are the two bases of human beings," she says. "On the one hand, I have desperate parents who despite having tried everything can’t have children. And on the other hand, there are these extremely poor women who really must provide for their families.”

It’s impossible to understand the deal “if we’re not in that situation ourselves,” Patel says. “All these holier-than-thou people should first try and find solutions for these unhappy families. Then, and only then, they can criticize me.”