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The following is a summary of “Clinical outcomes following preimplantation genetic testing for monogenic conditions: a systematic review of observational studies,” published in the February 2025 issue of Obstetrics and Gynaecology by MGenCouns et al. 

Researchers conducted a retrospective study to summarize clinical outcomes of preimplantation genetic testing for monogenic conditions, analyzing pregnancy and live birth rates, including subgroup outcomes of concurrent monogenic and aneuploidy screening. 

They searched 3 electronic databases (MEDLINE, EMBASE, and PubMed) from inception to May 2024. Eligible studies were quantitative audits, observational studies, and case series reporting clinical outcomes of preimplantation genetic testing for monogenic conditions. Only studies utilizing blastocyst biopsies with polymerase chain reaction-based or genome-wide haplotyping methods were aligned with current laboratory practices. Data extraction was followed by quality assessment using an adapted Joanna Briggs critical appraisal tool for case series. Clinical pregnancy and live birth rates were pooled with 95% confidence intervals (95% CI). Outcomes were compared between cases with and without concurrent preimplantation genetic testing for aneuploidy. 

The results showed 1,372 publications were identified, with 51 meeting eligibility criteria. Analysis of 5,305 cycles and 5,229 embryo transfers resulted in 1,806 clinical pregnancies and 1,577 births. Clinical pregnancy and birth rates were 34.0% [95% CI: 32.8%–35.3%] and 29.7% [95% CI: 28.5%–31.0%] per cycle, and 24.8% [95% CI: 23.6%–26.0%] and 21.7% [95% CI: 20.8%–23.1%] per embryo transfer. In cases with concurrent aneuploidy screening, clinical pregnancy and birth rates per cycle were 43.3% [95% CI: 40.2%–46.5%] and 37.6% [95% CI: 34.6%–40.8%], while per embryo transfer, they were 37.0% [95% CI: 33.9%–40.3%] and 31.8% [95% CI: 28.8%–35.0%]. Without aneuploidy screening, clinical pregnancy and birth rates per cycle were 32.5% [95% CI: 31.0%–34.1%] and 28.1% [95% CI: 26.6%–29.7%], and per embryo transfer, were 21.2% [95% CI: 19.8%–22.6%] and 18.6% [95% CI: 17.3%–20.0%]. 

Investigators concluded that preimplantation genetic testing for monogenic conditions demonstrated promising clinical outcomes. 

Source: sciencedirect.com/science/article/abs/pii/S0002937824010457