How Long Can Embryos Really Be Stored? What the Science and the HFEA Say

In 1984, the world's first baby born from a frozen embryo arrived in Australia. The embryo had been stored at -196 degrees Celsius for two months. Today, successful pregnancies have been reported from embryos stored for over 27 years.

The science is clear: at -196 degrees Celsius, all molecular motion stops. There is no ageing, no cellular degradation, no DNA damage. Biological time ceases. A 2020 study published in Human Reproduction found no difference in live birth rates between embryos stored for one year and those stored for nine years. The storage duration did not determine the outcome. The storage conditions did.

What the HFEA says

In the UK, embryo storage is regulated by the Human Fertilisation and Embryology Authority. The standard storage limit is ten years, extendable to 55 years in defined circumstances where one or both gamete providers has a condition likely to affect their fertility prematurely. This is a significant change from earlier limits and has practical implications for every IVF clinic storing patient embryos today.

What this means for clinics

A clinic storing embryos for a patient today may be responsible for those embryos for ten, twenty, or in exceptional cases fifty-five years. The cryogenic storage infrastructure must be maintained, monitored, and replaced across that entire period. This is not a logistical detail. It is a clinical and regulatory obligation.

Paul Hague, Director of Cryolab, has supplied cryogenic equipment to IVF clinics for over 40 years and introduced the controlled-rate freezer to Professor Robert Edwards, the Nobel Prize-winning pioneer of IVF: "A liquid nitrogen storage tank is a promise. And in reproductive medicine, that promise has to hold for years, sometimes decades."

Read the full article: cryolab.co.uk/how-long-can-embryos-be-stored/

Cryolab is a UK specialist supplier of IVF laboratory and cryogenic equipment, founded in 2000. ISO 9001:2015 certified. cryolab.co.uk