Performing genetic tests on embryos created using IVF could help women over the age of 35 conceive faster, a trial has found.
This could help reduce the “emotional toll” of repeated IVF cycles by slashing the risk of unsuccessful implantation and miscarriages, researchers suggest.
Preimplantation genetic testing for aneuploidy (PGT-A) is an IVF add-on that screens embryos for the correct number of chromosomes before they are implanted in the womb.
Aneuploidy is a genetic condition which means cells either have missing or extra chromosomes, compared to the normal 46, leading to miscarriages, birth defects and conditions like Down’s syndrome.
Women over 35 are at an increased risk for aneuploidy as egg quality declines with age, although PGT-A tests are not currently offered on the NHS.
The trial involved 100 women aged between 35 and 42 undergoing fertility treatment at King’s Fertility, half of which were given PGT-A tests.
Researchers found women in the group with PGT-A tests became pregnant in fewer embryo transfers.
There was also a higher live birth rate after up to three embryo transfers in the PGT-A group – 72% – compared to 52% in the group not given tests.
Dr Yusuf Beebeejaun, of King’s College London and King’s Fertility, said: “The number of women starting their family above the age of 35 is increasing and women in this age group are more likely to create embryos with the wrong number of chromosomes.
“This increases the risk of unsuccessful implantation and miscarriages.
“Our findings suggest that targeted use of PGT-A in this age group could help more women have a baby sooner, while also reducing the emotional toll of repeated unsuccessful cycles.”
Researchers suggest larger trials are now needed to confirm the findings, which have been published in the Journal of Clinical Medicine.
They conclude that the tests are “feasible” in women over 35, but suggest “specific focus needs to be placed on including patients over the age of 39, and lowering the threshold for high quality embryos from three to two” to increase eligibility.
The study also included mosaic embryos, which contain both normal and abnormal cells and are frequently encountered in IVF but rarely included in research.
Dr Sesh Sunkara, of King’s College London and King’s Fertility, added: “By focusing exclusively on women aged 35 to 42 and including mosaic embryos, we have addressed questions that previous studies have not adequately explored.
“While larger multi-centre trials are needed to confirm these findings, improving treatment efficiency with a shorter time to achieving pregnancy and live birth could reduce the physical and emotional burden of IVF for women of advanced reproductive age.”
One 39-year-old patient named Ana, who took part in the trial, gave birth following her first embryo transfer.
She said: “I believed PGT-A would give me the relative peace of mind, that my future pregnancies would succeed with a higher rate.
“Also, that syndromes associated to aneuploidy like Down’s were less likely.
“I believe PGT-A also helped my IVF journey, as I managed to become a mum to my beautiful child on my first attempt at embryo transfer. The fact that he was genetically normal, possibly made this more likely, as miscarriages are less frequent with genetically normal embryos.
“Having had a miscarriage in the past, for me it was important to minimise the risk of this happening again the most that I could. Having the opportunity to do this at King’s Fertility was a blessing, in my eyes.”
Dr Ippokratis Sarris, director of King’s Fertility and co-author of the study, said: “This research is a testament to the dedication and expertise of the team at King’s Fertility.
“Not only were all patients recruited and treated here, but the embryology work was also carried out by our laboratory staff.
“We are proud to have led this pioneering trial, which addresses one of the most important questions in IVF treatment for women over 35, and we look forward to building on these findings in larger, multi-centre studies.”
