Fertility clinics should prioritise women over 40 as they work through the backlogs caused by the Covid-19 pandemic, researchers have said.
They should also prioritise couples with a known cause of infertility, experts at the University of Aberdeen added.
The delays in care could lead to a significant reduction the proportion of babies born to women over 40 as well as those with a known cause of infertility, who need treatments like IVF, they said.
A new study has estimated the impact of delays to care.
They said that a delay in starting IVF reduces success rates in all couples but they have estimated that the effects could be more pronounced in some groups.
Their new study, published in the journal Human Reproduction, used data from almost 10,000 women who had undergone IVF treatment to explore the impact of delays.
The findings show the potential impact of a delay in treatment of six months and 12 months on five age categories, from under-30 year olds, to 40-42 year olds.
They found that the older the age group, the more pronounced the effect.
Among those aged 40 to 42 – the oldest cohort studied – a six-month delay would reduce live births by 11.8%, the authors estimated.
And a 12-month delay would reduce chances by 22.4%.
They also estimated that the chances of couples with a known fertility problem could reduce significantly.
They said that the effect was less detrimental among those with unexplained infertility.
Professor Abha Maheshwari, clinical director of the Aberdeen Fertility Centre and one of the authors of the study said: “A delay in starting IVF reduces success rates in all couples.
“For the first time, we have shown that while this results in fewer babies in older women and those with a known cause of infertility, it has a less detrimental effect on couples with unexplained infertility, some of whom conceive naturally whilst waiting for treatment.
“Post Covid-19, clinics planning a phased return to normal clinical services should prioritise older women and those with a known cause of infertility.”