Her birthday may be October 2020, but the birth of Molly Gibson has actually been 27 years in the making.

US baby Molly has set a new record for the longest-frozen embryo to have resulted in a birth.

Her birth breaks a record set by her older sister, Emma.

Molly’s parents had been trying to conceive for years with no success. Then her grandparents saw a story on embryo adoption on a local news station.

Molly’s mother, a school teacher, and her husband, a security analyst, got in contact with the National Embryo Donation Center (NEDC).

The NEDC is a Christian non-profit organisation, based in Knoxville, that stores frozen embryos that IVF patients no longer need and chose to donate.

Families like the Gibsons can adopt unused embryos.

The NEDC conducts around 200 transfers in the United States each year.

Couples who decide to adopt an embryo can decide if they would like a anonymous adoption or an open one, which would allow for contact with the donor family.

Families can choose from donor profiles, in much the same way people can choose sperm or egg donors.

But, like many couples, the Gibsons were just thrilled at being able to become parents.

“We did not care what this baby looked like, where it came from,” Ms Gibson told media.

After their first embryo adoption, Ms Gibson gave birth to Emma in 2017.

Three years later, Emma’s sister Molly was born.

Molly and Emma are genetic siblings, with both embryos frozen in 1992.

In 1992, their mother was around one year old.