Genetic Testing of IVF-Created Embryos Speeds Up Conception in Women Over 35

This increases the risk of miscarriage and unsuccessful implantation, leaving many to endure repeated cycles. Current guidelines by the National Institute for Health and Care Excellence (NICE) do not recommend routine genetic testing of embryos, based largely on evidence from younger women with lower risk, forcing older women to seek private options or forgo testing altogether. Now, a new study suggests that targeted testing may help.

Researchers from King’s College London (London, UK) and collaborators led the first randomized controlled trial worldwide focused exclusively on women aged 35–42. The trial evaluated Preimplantation Genetic Testing for Aneuploidy (PGT-A), which screens IVF embryos for chromosomal abnormalities before transfer. Unique to this study, mosaic embryos, containing both normal and abnormal cells, were also included, addressing a gap in previous research.

The unblinded pilot trial, conducted between June 2021 and June 2023 at King’s Fertility, recruited 100 women aged 35–42 undergoing IVF. Participants were split into two groups, with 50 receiving PGT-A and 50 serving as controls. Both the clinical treatment and embryology work were carried out at King’s Fertility, ensuring consistency in patient care and laboratory analysis.

The findings, published in the Journal of Clinical Medicine, showed that women in the PGT-A group achieved pregnancy in fewer transfers, with a cumulative live birth rate of 72% after up to three embryo transfers, compared to 52% in the control group. Although the difference did not reach statistical significance due to the small sample size, the trend suggests a potential benefit. The study demonstrated the feasibility of a larger multi-center randomized trial to confirm these findings.

The researchers emphasized that reducing the time to conception could greatly improve efficiency in IVF treatment for older women, lowering both the physical and emotional burden. If validated in larger studies, the targeted use of PGT-A could become a crucial tool in enhancing success rates for women over 35.

“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,” said Dr Yusuf Beebeejaun, first author. “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.”