A Spanish fertility clinic launched a scheme on Thursday to let women adopt frozen embryos to save them from scientific research just as Spain makes research with embryo stem cells fully legal.

Tens of thousands of embryos, left over from fertility treatment, are currently frozen in Spain.

A decree due this month will allow scientists to use them for research on stem cells which scientists say could hold cures for diseases such as Alzheimer’s.

The Barcelona clinic wants to create an alternative by allowing women to be implanted with embryos and raise them as their own children.

“We are in favour of investigation (with embryos) but we think ... if we have embryos from healthy parents it could be good to give them the option of being born and living,” Marisa Lopez-Teijon, gynaecologist at the Institut Marques, said.

Infertile couples can already receive embryos from other couples but they tend to ask for embryos with certain characteristics that match their own, like race and hair colour.

This scheme aims to find homes for the embryos, not babies to specification for couples, she said, adding there were an estimated 60,000 to 80,000 frozen embryos in Spain.

“There are a lot more embryos than sterile couples that want, that need, embryos,” she told Reuters by phone.

Part of the Institut Marques clinic’s motive is to deflect criticism that they expect to receive from opponents of stem cell research when the decree is issued.

Fertility treatment usually produces left-over embryos which are not implanted and couples can choose what will happen to them. However, Lopez-Teijon said in practice many parents had left the decision to the doctors.

“What our clinic wants to do is pass on, share the responsibility that we as doctors and people have with society ... Come here and implant yourself with one if you don’t want it to be destroyed,” she said.

She declined to comment on who might use the service but thinks it could be less controversial for a single woman to say that she had saved an embryo than that she had been inseminated by an unknown donor.

Spain, where increasingly liberal views coexist with traditional Catholicism, legalised stem cell research last year - with a string of conditions - but it will not be completely legal until a decree detailing regulation is issued this month.