Embryos derived from single pronucleus are suitable for preimplantation genetic testing

Area of Science:

• Reproductive Medicine
• Genetics
• Embryology

Background:

• Preimplantation genetic testing for monogenic disorders (PGT-M) is crucial for inherited disease prevention.
• Embryo development and viability can differ based on pronuclear number (1PN vs. 2PN).

Purpose of the Study:

• To compare PGT-M results and treatment outcomes between embryos derived from single pronuclei (1PN) and two pronuclei (2PN).
• To evaluate the clinical utility of PGT-M in 1PN embryos.

Main Methods:

• Retrospective cohort study of 351 IVF-PGT-M cycles (January 2018-December 2022).
• Analysis of embryo biopsy, molecular testing, and clinical outcomes for 1PN and 2PN-derived embryos.
• Comparison of blastocyst development rates and PGT-M success rates.

Main Results:

• 1PN embryos exhibited significantly lower developmental potential, with fewer blastocysts and top-quality blastocysts compared to 2PN embryos.
• PGT-M success rates (unaffected embryos) were lower for 1PN (47.1%) versus 2PN (65.5%), with higher abnormal results in 1PN (39.6%).
• Despite lower rates, 1PN embryo transfer resulted in a 20.8% clinical pregnancy and 16.7% live birth rate.

Conclusions:

• While 1PN embryos have reduced developmental potential and PGT-M success, they can still lead to successful pregnancies.
• Applying PGT-M to 1PN embryos is recommended to enhance cumulative clinical pregnancy and live birth rates in IVF treatments.