Aneuploidy rates and likelihood of obtaining a usable embryo for transfer among in vitro fertilization cycles using preimplantation genetic testing for monogenic disorders and aneuploidy compared with in vitro fertilization cycles using preimplantation genetic testing for aneuploidy alone

Abstract

Objective: To compare aneuploidy rates among in vitro fertilization (IVF) cycles using preimplantation genetic testing for monogenic disorders (PGT-M) and aneuploidy (PGT-A) compared with IVF cycles using PGT-A alone, and to determine the likelihood of obtaining at least one usable embryo in cycles using PGT-M+PGT-A compared with cycles using PGT-A alone.

Design: Retrospective cohort study.

Setting: Single genetics laboratory.

Patient(s): All IVF cycles for patients aged 18-45 undergoing PGT-A with or without concurrent PGT-M at a single genetics laboratory from November 2019 to March 2023.

Intervention(s): Use of PGT-M+PGT-A vs. use of PGT-A alone.

Main outcome measure(s): Per cycle aneuploidy rate stratified by age, and per cycle likelihood of obtaining at least one usable embryo stratified by age and inheritance pattern of monogenic disease.

Result(s): A total of 72,522 IVF cycles were included; 4,255 cycles (5.9%) using PGT-M+PGT-A and 68,267 cycles (94.1%) using PGT-A alone. The PGT-M+PGT-A group was younger than the PGT-A alone group (<35 years old: 56.1% vs. 30.5%). The majority of PGT-M cycles were performed for autosomal dominant pathogenic variants (42.4%), followed by autosomal recessive (36.5%), X-linked dominant (13.3%), and X-linked recessive (7.5%). The median number of embryos biopsied was higher in PGT-A alone compared with PGT-M+PGT-A cycles for patients aged <35, but it was equivalent in all other age groups. Age stratified aneuploidy rates did not significantly differ between PGT-M+PGT-A compared with PGT-A alone cycles. The probability of having a usable embryo declined with increasing age across all inheritance patterns. Compared with PGT-A alone, PGT-M+PGT-A cycles for patients aged ≤40 across all inheritance patterns were significantly less likely to yield a usable embryo, except in cycles for autosomal recessive diseases in the 38-40 age group and X-linked recessive diseases in the 35-37 age group. There were no consistent differences seen between groups in patients over 40. Cycles for patients with autosomal dominant diseases had the lowest likelihood of yielding a usable embryo for patients aged <43.

Conclusion(s): In vitro fertilization cycles using PGT-M+PGT-A have similar age-specific aneuploidy rates to those using PGT-A alone. Cycles for patients ≤40 using PGT-M+PGT-A are significantly less likely to yield a usable embryo compared with those using PGT-A alone.

Keywords: Aneuploidy; PGT-M; usable embryo rate.