World’s ‘oldest baby’: what a 30-year-old embryo tells us about the future of fertility

A baby born in the US has made headlines for a surprising reason: they came from an embryo that had been frozen for more than 30 years — setting a new world record.

The embryo was created and stored in 1994, back when Bill Clinton was US president and the internet, email and mobile phones were still in their infancy. Now, decades later, that embryo has become a living child. But how is this possible – and what does it mean for the future of fertility treatment?

Freezing embryos is a common and effective part of in vitro fertilisation (IVF). During IVF, multiple eggs are fertilised, and any unused embryos can be frozen and stored for future use. Globally, thousands of embryos are placed in long-term storage each year – and as the demand for fertility treatment grows, so too does the number of embryos in storage.

But once a person or couple finishes treatment, the question of what to do with unused embryos can become complicated. As this case in the US illustrates, families and circumstances change...