The 10-year limit for storing eggs frozen for social reasons could be scrapped to give people concerned about declining fertility more time and options, says a UK ethics body.
Nuffield Council on Bioethics says consumers also need more data on costs and success rates to inform choices.
It criticises methods used by some companies to sell the service.
The government is assessing the 10-year rule. Eggs frozen for medical reasons can already be stored for longer.
Sperm can be stored indefinitely.
The Nuffield team says research suggests women can feel under pressure to freeze their eggs to avoid regrets later in life, and it is important that marketing strategies do not exploit these anxieties.
Some services have used Prosecco-fuelled marketing events and computer algorithms to target women online with adverts, says Nuffield.
Egg freezing paid for by companies as an employment benefit is another cause for concern.
While some may view it as a workplace “gender equaliser” with positive effects on women’s salaries, it might also push women to delay motherhood to show commitment to their career, says the team.
The NHS only funds egg freezing for medical reasons, not social ones.
Someone who has their eggs frozen for medical reasons – in advance of cancer treatment, for example – can apply to have them stored for up to 55 years.
Nuffield says there appear to be few arguments against increasing the storage limit for social egg freezing.
Dr John Appleby, lecturer in medical ethics at Lancaster University, said: “The UK’s 10-year egg freezing rule for social egg freezing is not fit for purpose and this briefing highlights how we have very little reason for maintaining it any longer.”
Sarah Norcross, from the assisted conception debate group Progress Educational Trust, said: “With more women than ever choosing to freeze their eggs, it is time for the law to be changed.”
Frances Flinter, Nuffield Council member and emeritus professor of clinical genetics at Guy’s and St Thomas’ NHS Foundation Trust, said: “It’s vital for women thinking about freezing their eggs to be able to make informed choices.
“To do this, they need easy access to data on their chances of success across various stages of the process – from freezing and thawing eggs, to having a live birth. But they also need clinics to be frank about the process, and about what is known and unknown about egg freezing.”
Egg freezing facts
According to the Human Fertilisation and Embryology Authority, around a fifth of IVF treatments using a patient’s own frozen eggs result in the birth of a baby, based on figures for 2017.
Not all eggs survive thawing. If they do, the chance of a live birth depends to a large extent on the age of the woman when the eggs were collected, with success more likely for those under 35.
The average cost of having eggs collected and frozen for social reasons is £3,350, with additional £500-£1,500 costs for medication.
Storage costs are extra and tend to be £125-£350 per year.