ADVANCES IN MEDICAL SCIENCE that make it possible for a woman to carry a genetically-unrelated child are having a profound effect on the practice of commercial surrogacy in the United States. Legal specialists and surrogacy experts agree that gestational carriers are fast replacing so-called "traditional surrogates."

"It is a very different psychological hurdle to navigate if you are genetically related to the child you're carrying," says Andrea Braverman, chief psychologist at Pennsylvania Reproductive Associates, the infertility program Justy works with. Braverman screens candidates to make sure they can handle both the rigors of pregnancy and giving up the child.

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"They feel that psychologically they are safer if they are very clear saying, 'Hey, it's her egg and his sperm,'" Braverman says.

Andrea Braverman, chief psychologist at Pennsylvania Reproductive Associates in Philadelphia, screens candidates for the clinic's "gestational carrier" program.
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No one knows how many babies are born through surrogacy each year - experts put the number in the hundreds. Dozens of agencies and brokers have popped up around the country that will match surrogates and clients. Unlike adoption, surrogacy is virtually unregulated. Some agencies are staffed with doctors, lawyers, and mental health professionals. Others are one-person operations run by former surrogates or entrepreneurs. A recent scan of the World Wide Web found more than 80 surrogacy programs in the US. There's even an on-line surrogacy store that sells books, videos, and t-shirts.

With legal, medical, psychological, and administrative fees, the costs to an infertile couple can easily top $50,000. Couples come from around the world to the US to find surrogates because the practice is often illegal in their home countries. Psychologist Hilary Hanafin, of the Center for Surrogate Parenting and Egg Donation in Los Angeles, says even though more women appear willing to sign up as gestational carriers, demand still far exceeds supply. Hanafin points out that conceiving with someone else's embryo is far more taxing than the simple artificial insemination used in traditional surrogacy.

"[Gestational carriers] inject themselves with hormones every day for four months. There's a lot of ultrasounds, a lot of trips to the doctor's office, a much higher rate of multiple births - twins and triplets - so I wouldn't say the interest in that program has skyrocketed," Hanafin says. The Los Angeles program oversees 30-40 pregnancies each year and has a waiting list more than six months long to match surrogates with infertile couples. The center is probably the largest agency in the country.

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