How does genetic testing affect IVF outcomes for older mothers?

This study looked at genetic testing prior to implantation in women over 37 undergoing in vitro fertilization (IVF). It found that in couples that chose genetic testing, the miscarriage rate was much lower, and the overall likelihood of a live birth was similar.

When sperm and eggs develop, the number of DNA chromosomes is halved from 46 to 23. If this happens incorrectly, the sperm or egg can have the wrong number of chromosomes. Chromosomal abnormalities happen more frequently in older parents, particularly in mothers over 35. 

During in vitro fertilization (IVF), it is possible to test the number of chromosomes of the embryo. Preimplantation genetic testing (PGT-A) may have an improvement in pregnancy outcomes. It is important to evaluate the outcomes of PGT-A in couples undergoing IVF.

This study looked at couples being treated with IVF with women between 38 and 44 years old. 2538 couples chose to complete IVF without PGT-A (the control group). 308 couples had PGT-A. 106 couples initially intended to undergo PGT-A but stopped due to having fewer than 5 embryos.

Out of 308 couples in the PGT-A group, 55 (17.9%) did not have an embryo suitable for PGT-A testing. These couples did not undergo embryo transfer. Among all embryos tested, 40.8% had normal chromosomes. 101 of the couples did not have a normal embryo. The remaining 152 PGT-A couples had a single chromosomal normal embryo transferred. Women in the control group had one or two embryos transferred.

Among PGT-A women who had an embryo transfer, 46.3% had a positive pregnancy test. This compared to 31.1% of the control group. Women in the PGT-A group were 81% less likely to have a miscarriage. 11% of women in the control group had a multiple pregnancy. No women with PGT-A had multiple pregnancies, due to using a single embryo transfer. Per embryo transfer, significantly more women in the PGT-A group had a live birth (40.3% vs 19.5%). Looking at the entire IVF cycle, women had similar rates of live birth with and without PGT-A testing (26.3% vs 24.0%).

This study concluded that PGT-A improves the outcomes of couples undergoing IVF.

This study had a short follow-up period. 

If you have concerns regarding IVF and PGT-A, please discuss this with your doctor.