When Liz Krainman and her husband Kevin found out they couldn’t conceive naturally, they considered the typical list of alternative methods, from in vitro fertilization treatments to traditional adoption. Then they heard about embryo donations, and Krainman immediately knew it was the right fit.

“I wanted to experience pregnancy. I wanted to offer love to a child who needed it. I wanted to experience birth,” Krainman told People. Krainman gave birth to a baby girl this summer using a frozen donor embryo.

The Krainmans aren't on the fringe here. Just days before their story appeared on People.com, psychotherapist Maya Grobel Moskin wrote about her lengthy infertility journey on the New York Times' parenting blog, Motherlode. She tried "old fashioned" remedies before moving on to fertility drugs, artificial insemination, IVF, and even a donor egg from her sister. She also considered traditional adoption, but it would be another $30,000. So she went with a frozen donor embryo, which cost about $7,000. "This little baby popsicle seemed like our best choice," Moskin wrote.

But where do people even get the embryos and how does the process work? Here, a few things you should know.

How does it work?

Embryo donation is the transfer of a non-autologous embryo, which means that the person receiving the fertilized embryo isn't connected to either the egg or sperm donor, according to Jeff Keenan, MD, of the National Embryo Donation Center. It's kind of like using a regular donor egg, except it's already been fertilized—then frozen and thawed.

The donated embryos typically come from another couple with frozen embryos left over after undergoing IVF treatments. These families have a few options: They can continue to pay to store the embryos in liquid nitrogen indefinitely; discard the embryos, donate them to scientific research, or find a couple like the Krainmans who want to have a baby.

According to People, Krainman found two women who offered to donate their embryos: one through the site MiraclesWaiting.org and one via a traditional adoption forum. The first two attempts at pregnancy ended in miscarriage, but on the third try, she had an embryo transferred from each donor. One resulted in a successful pregnancy, giving her and her husband their daughter, Sammy, who is now 4 months old. The embryo that became Sammy came from a couple that underwent 5 unsuccessful rounds of IVF and was in cryogenic storage for 7 years, from 2006 to 2013.

How common is it?

According to Dr. Keenan, there are now more than 1,000 embryo donations in the U.S. each year. While the first embryo donation happened back in the 1980’s, it didn’t become a more popular choice until a decade later.

“It’s becoming more and more common as people are accepting IVF as a possibility,” said Shahin Ghadir, MD, FACOG, of the Southern California Reproductive Center. The more people trying IVF, the more embyros on ice.

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How much does it cost?

Embryo donation may appeal to couples struggling with infertility because it can have a lower cost compared to traditional adoption or IVF. According to AdoptionHelp.org, adopting a newborn from a non-profit agency costs between $10,000 and $25,000, while adoption through an attorney can go up to $30,000.

There are still costs associated with receiving a donated embryo, from the price of testing the donors for infectious diseases, drawing up a legal contract between the donor and the recipient, to actually shipping the embryo to its destination.

Krainman told People that embryo donation typically costs somewhere between $3,500 to $12,000 per attempt. In their case, the Krainmans paid between $6,000 and $7,000 for each of their three attempts, and they had partial insurance coverage. Dr. Keenan says using an embryo from an anonymous donor is even less expensive: usually about $1,200 to $2,000 less. And note that donors shouldn't receive compensation for the embryos, per the American Society of Reproductive Methods (ASRM).

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What are the legal implications?

Both Krainman and many fertility web sites refer to this transfer as an "embryo adoption," which Dr. Keenan says is more of a shorthand used by the donors and recipients. The ASRM prefers the term "embryo donation," because an embryo is not considered a “fully entitled legal being” until birth, according to the ASRM’s Ethics Committee, and would not have the same rights as a newborn adopted traditionally. This means people need unique paperwork.

Donation organizations help couples create legal agreements per ASRM guidelines in which the donor couple relinquishes their parental rights and transfers those rights to the adopting family before donation. The National Embryo Donation Center says the adoptive couple will be recognized as the legal parents on the birth certificate, but it's probably a good idea to have a lawyer look over the informed consent documents.

What about the baby?

Similar to traditional adoption, patients who decide to use a donated embryo also have to consider how to tell their child about their biological parents. Dr. Keenan recommends counseling with the parents prior to the procedure to ensure that they understand the effect this can have on the child.

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