A baby who was frozen as an embryo for more than two decades has been born to a woman in the United States.

The embryo was cryopreserved for 24 and a half years, making it the longest ever frozen embryo to be successfully born, according to research staff at the University of Tennessee Preston Medical Library.

Emma Wren was born on November 25th to Tina Gibson (26) from East Tennessee.

As an embryo, she was frozen on October 14th 1992, about 18 months after Mrs Gibson was born.

Embryologist Carol Sommerfelt revealed when the Gibsons were shown a picture of their embryos as they were being transferred, Mrs Gibson said: "These embryos could have been my best friends."

In March last year it was thawed at the National Embryo Donation Centre (NEDC) in Knoxville, Tennessee, and a transfer was performed on Mrs Gibson, then 25-years-old, two days later.

Benjamin Gibson, the baby's father, said: "Emma is such a sweet miracle.

"I think she looks pretty perfect to have been frozen all those years ago."

Ms Sommerfelt added: "It is deeply moving and highly rewarding to see that embryos frozen 24 and a half years ago using the old, early cryopreservation techniques of slow freezing on day one of development at the pronuclear stage can result in 100% survival of the embryos with a 100% continued proper development to the day-three embryo stage."

Dr Jeffrey Keenan, the NEDC's medical director who performed the transfer, said: "The NEDC has been privileged to work with the Gibsons to help them realize their dreams of becoming parents.

"We hope this story is a clarion call to all couples who have embryos in long-term storage to consider this life-affirming option for their embryos."

The NEDC is a faith-based centre which has helped nearly 700 women become pregnant through embryo implantation.

Embryos have been donated to the NEDC from all 50 states in the US.