Twins have been born from embryos that had been frozen for 30 years, the longest any embryo has been frozen before leading to a live birth to date.

The embryos were created for an anonymous married couple using IVF in 1992. The man was in his 50s and the couple reportedly relied on a 34-year-old egg donor. The embryos were kept at a fertility lab on the West Coast until 2007, when the couple who created them donated them to the National Embryo Donation Centre (NEDC) in Knoxville, Tennessee, hoping that another couple might choose them.

They were selected by couple Philip and Rachel Ridgeway who had requested that the non-profit Christian NEDC provide embryos that had 'special consideration', meaning they had proved difficult to place with couples who wished to use a 'donated' embryo. 'We weren't looking to get the embryos that have been frozen the longest in the world,' Philip Ridgeway said. 'We just wanted the ones that had been waiting the longest.'

Two of the five thawed embryos were nonviable. Of the three that were transferred, two successfully implanted 29 years and ten months after they were frozen, resulting in the live birth of Lydia and Timothy Ridgeway on 31 October'. The couple considers the twins to be their 'oldest children' even though they are less than a month old: they already had four naturally-conceived children aged eight, six, three and one.

Theoretically, embryos can remain in cryostorage in liquid nitrogen at a temperature of -196C indefinitely. The birth of Lydia and Timothy is further evidence of this theory. On 1 July 2022, the rules on how long you can store eggs, sperm or embryos in the UK changed. Before this date, people in the UK could usually only store their embryos for up to ten years (though there were a few medical exceptions allowing for 55 years).

The law now permits storage of embryos for use in treatment for up to a maximum of 55 years from the date the embryos are first placed in storage.

Sources and References

• 23 November 2022. BBC
  Twins born from embryos frozen 30 years ago

• 21 November. CNN
  Parents welcome twins from embryos frozen 30 years ago

• 22 November 2022. Huffington Post
  World's 'oldest' babies born from embryos frozen 30 years ago

• 21 November 2022. Daily Mail
  Parents welcome 'oldest' twins in the world after they were born from embryos frozen THIRTY years ago – when George W Bush was president and Vanessa Williams topped the charts

• 23 November 2022. Independent
  Parents welcome twins from embryos frozen in 1992

• 23 November 2022. ABC News
  Twins born from embryos frozen 30 years ago