By Isa Soares

Madrid, Spain (CNN) - As the Spanish economic crisis deepens and unemployment soars, those struggling to make ends meet are increasingly selling their eggs and sperm to bring in some extra cash.

This female donor doesn't want to be identified for fear of being stigmatized. She's at the Tambre Clinic in central Madrid to donate her eggs, a process she's been through four times before.

"The first donation I made, when I came to the clinic, I was accompanied by my mother," she said.

Now she's come alone. She knows that while donating will help others start a family, it will also help her family survive financially.

"I work at a house, I also do manicures and I work as a cleaner," she said.

Her husband works as a taxi driver, but the economic stress in Spain has severely hurt their income. With unemployment topping 24 percent in Spain, extra work is hard to find. So she made the decision to begin donating her eggs for cash, a process that requires a series of hormone injections and the surgical removal of the eggs.

"Once I made two donations, two in one and I got 3,000 Euros," she said.

Women receive up to 1,000 Euros per donation, but the process is long, painful and carries risks.

Once accepted as donors, men can give sperm once a week over three months and receive up to 50 Euros each time.

The 1,000 Euro payment makes a substantial difference to her family's income.

"When you don't have enough money, you save it, and when you need it, you take the donation money and you pay all the bills," said the woman.

But this is her fifth donation and it will be her last.

"They only recommend a maximum of six donations, so it does not affect your health," said the woman.

Her doctor, Rocio Nunez, says she's been surprised by the number of donors walking into her clinic, however the industry is closely regulated, so they don't take everyone who comes through the door. Apart from physical testing, potential donors must also undergo thorough psychological evaluations.

"The number of donors increased because there are more people who need money to survive," said Dr. Nunez.

According to the body that monitors reproduction clinics in Spain, in the last year alone there's been an almost 30 percent increase in egg and sperm donations, and once finished here, some go elsewhere, selling their hair or even breast milk.

Either way you look at it, these ar signs of hardship, desperation and need.

CNN