Los Angeles's Fertility Clinic has offered parents the opportunity to pay in order to select the gender of their babies for several years. And soon parents can also choose the eye and hair color of their children. In L.A., some are calling these customized kids "designer babies."

The service will cost $18,000 per baby and will be available only to couples seeking in-vitro fertilization. The clinic says they have already received five or six requests for the service and expect the first “designer baby” to be born next year.

Dr. Jeffrey Steinberg has already helped thousands of couples choose their child's gender at his fertility institutes in Manhattan and Los Angeles. Within six months, he says, the clinic will offer the new service. The procedure is called pre-implantation genetic diagnosis, or PGD. It's been used by fertility doctors for years to screen embryos in the lab -- mostly for parents who want to reduce the chances of carrying a baby with life-threatening diseases.

According to Steinberg, the technology behind genetic screening has progressed to the point where parents can almost custom-design their babies. The science is based on a lab technique called preimplantation genetic diagnosis, or PGD. Doctors then select an embryo free from rogue genes - or in this case an embryo with the desired physical traits such as blonde hair and blue eyes - to continue the pregnancy, and discard any others.

The technology was initially created to screen for disease, then used for gender selection. Now Los Angeles's Fertility Clinic--with offices in L.A., New York, and Mexico--plans to allow parents to select physical traits as well.