CHAROTTE -- Tight economic times have some women considering selling their eggs for cash. Fertility clinics are reporting the number of women wanting to donate is up 50 percent from last year.

"I think the economy has something to do with it,” said Pat Buetow, a nurse at Reach fertility clinic. “I am even getting calls from people who donated years ago who and they want to donate again."

At Reach, accepted donors earn $4,000 per egg retrieval.

"Since last year, we've probably seen 1,000 applications," said Buetow.

But a woman can't just walk into a fertility clinic, say she wants to donate an egg and immediately get cash on the spot. Donating an egg is a long procedure, one with state and national guidelines, that can take months to complete.

"That person goes through multiple blood studies to make sure she is a healthy egg donor, a psychological study, a genetic history is taken, a physical is also done," explained Dr. Richard Wing, of Reach.

Wing says only 10 percent of applicants are accepted.

Both donors and recipients stay anonymous during the process. Reach’s egg donors must be between the ages of 21 and 32 years old. They say the majority of those who donate are college students or working professionals.

More than 10,000 babies are born each year from commercial egg donation.