An embryo selection technique that can cost an additional £850 on top of IVF treatment bills does not increase the chances of having a baby, a large trial has found.
TLI (time-lapse imaging), which involves taking timelapse videos of embryos in an incubator as they grow, is sold as an add-on service by many UK private fertility clinics.
Some practitioners believe it can help in selecting the best embryos for implantation, despite the benefits of TLI remaining unproven.
But new trial data from 1,500 women undergoing fertility treatment has now revealed TLI does not improve the odds of a live birth when compared to using other standard IVF approaches.
Dr Priya Bhide, from the Women’s Health Research Unit at Queen Mary University of London, who led the trial, said the results show that theoretical benefits do not always translate into improved clinical outcomes.
Dr David Chan, lab director at the Prince of Wales Hospital at The Chinese University of Hong Kong, said clinics should focus on lab equipment that has “a direct, measurable impact on live birth rates” instead of investing in expensive TLI machines.
Unlike conventional methods, where embryos are taken out of incubators for screening, the TLI technique involves remote monitoring using cameras.
This means TLI embryos are not subject to temperature fluctuations, humidity and other elements that might affect development.
Separate research by Dr Bhide and her colleagues uncovered 71 out of 106 private fertility clinics in the UK offer TLIs, with costs ranging from £300 to £850.
However, in recent years, the Human Fertilisation and Embryology Authority (HFEA), the UK’s fertility regulator, has raised concerns about this unproven screening method.
To find out more, the researchers designed a clinical trial with more than 1,500 women undergoing IVF at seven centres in the UK and Hong Kong.
The women were split into three groups: the first received TLI screenings for their embryos as an add-on to their fertility treatment, the second had the standard assessment – where the embryos were analysed remotely as a static snapshot (undisturbed culture), and the third (control) group underwent conventional assessment where embryos were taken out of the incubator and observed under a microscope.
As this was a double-blind trial, neither the researchers nor the patients knew which treatment the women received.
Results showed live birth rates were 33.7% in the TLI arm, 36.6% in the undisturbed culture arm and 33.0% in the control arm.
Dr Bhide said: “Our trial suggests that TLI does not improve the odds of live birth in women having IVF and ICSI treatments.”
Commenting on the findings, Professor Tim Child, HFEA authority member and chairman of the HFEA scientific and clinical advances advisory committee, said: “People undergoing fertility treatment are often willing to do everything they can to improve their chances of success.
“However, the HFEA has raised concerns for several years about some clinics offering unproven extras at an additional cost, known as add-ons, claiming to increase the chance of having a baby.
“Although there are particular treatment add-ons that may be potentially beneficial in certain specific patient groups, our rating system launched in 2023 shows that time-lapse imaging and incubation has no effect on treatment outcome – a finding that is supported by the trial led by the Women’s Health Research Unit at Queen Mary University of London.”
He said the HFEA add-on rating system can help patients and their partners make better-informed decisions about fertility treatments.
Professor Child said: “It’s often the case that extra rounds of standard treatment can be more effective than paying for unproven or ineffective add-ons.”
Sarah Norcross, director of the Progress Educational Trust (PET), a charity that strives to improve choices for people affected by infertility and genetic conditions, said: “For more than a decade, we have seen claims that using time-lapse imaging for embryo selection can improve the chance of a live birth by 50% or more.
“Finally, we have a thoroughgoing, double-blind, randomised controlled trial that can detect meaningful differences in live births, when time-lapse imaging is used for embryo culture and selection.
“Importantly this trial has found that time-lapse seems to make no difference.
“The lesson here is that patients should be sceptical, whenever any claim is made that any technology or add-on can improve chances of IVF success.
“Certainly, clinics should not be charging patients extra for fertility treatment if time-lapse imaging is used.”
