A recent scientific development could lead to new infertility treatments and bring same-sex couples one step closer to conceiving a child with both their DNA.

Dr. Azim Surani, a prominent scientist at the University of Cambridge, said he and his colleagues made a major discovery in mimicking the way the body creates sperm from stem cells. During a conference in London last month, he discussed the results of his not-yet-published study. He claimed his team had witnessed embryonic cells undergo a process called “erasure” in a lab. The process is necessary to prevent DNA mutations from being passed to offspring.

Dr. David Albertini, a scientist at the Center for Human Reproduction, called the discovery “a milestone in a very long process.”

He said that the finding offers “a glimmer of hope,” but that much more needs to be understood before a mature sperm can be created in a lab. He said scientists still need to figure out how to make embryonic cells develop into sperm and eggs in a complex process known as “meiosis.”

“To think that we could recapitulate the whole process outside of the body and end up with a sperm cell that could then be used to fertilize an egg, that’s an ambitious goal,” Albertini said.

Albertini noted scientists in China and Japan created artificial sperm and eggs from stem and skin cells that produced healthy mice pups. But in humans, he stressed, the process would be much longer, fragile and more complex — and there would be a slew of safety, ethical and legal concerns to contend with.

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If creating sperm and eggs from stem cells or skin cells does become a reality, it could have a profound impact on same-sex couples and heterosexual couples struggling with infertility. In theory, a skin cell from a woman in a same-sex relationship could be used to produce sperm, which could in turn be used to fertilize her partner’s egg.

"To think that we could recapitulate the whole process outside of the body and end up with a sperm cell that could then be used to fertilize an egg, that’s an ambitious goal." Dr. David Albertini

If this technology is one day available, Albertini said it would be very expensive. Today, he said, assisted reproduction already costs thousand dollars and isn’t always covered by insurance.

“I would think that doing something like this, you’re adding at least $10,000 by today’s standards,” he added.

On the legal side of things, however, it could overcome a major hurdle for same-sex couples seeking to have children, since they would both be the biological parents.

When same-sex couples use donated sperm or eggs, the nonbiological parent may need to adopt the child to be recognized as a legal parent of that child, depending on state law, according to Beth Littrell, an attorney for the LGBTQ nonprofit Lambda Legal.

“It’s an expensive, burdensome and lengthy process,” she said.

For heterosexual couples, she noted, the same rules don’t apply — even if the father is not the biological parent.

“Men can sign an affidavit of paternity,” Littrell explained. “They don’t have to do anything more than sign a piece of paper regardless of whether they have a biological relationship, and they are recognized as a legal parent. States have not applied those same avenues to parentage to same-sex couples.”

Different states have different laws governing adoption, Littrell said, and the process can take anywhere from weeks to a year. Some couples do not have the money to adopt, she added, or may simply find the process too exhausting. In cases where anonymous sperm is donated to a lesbian couple, for instance, courts may decide the sperm donor has parental rights, which have to be extinguished before a legal adoption can take place, she said.

But adoption is necessary for legal purposes, according to Littrell. If the biological mother dies before giving birth or before the adoption process is finished, or if the couple divorces before an adoption happens, she explained, the nonbiological parent may have no legal rights to the child. For same-sex male couples, where a surrogate is involved, the process can be even more complicated.

While the recent research out of Cambridge brings same-sex couples one step closer to biological parenthood, Albertini still thinks it’s “a long way off in the future.”

In the meantime, advocates like Littrell are working on making laws around parentage fairer for same-sex couples.

“It’s a long road to equality,” Littrell said. “We’re along that road. We’ve made a lot of progress, but we’re not there yet.”

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