Multiple cryopreservation-warming cycles, coupled with blastocyst biopsy, negatively affect IVF outcomes

Area of Science:

• Reproductive Medicine
• Embryology
• In Vitro Fertilization (IVF)

Background:

• Blastocyst biopsy for preimplantation genetic testing for aneuploidy (PGT-A) is a common IVF procedure.
• The impact of repeated cryopreservation and warming cycles on IVF outcomes, especially after biopsy, requires further investigation.

Purpose of the Study:

• To evaluate the effect of multiple cryopreservation-warming cycles combined with blastocyst biopsy on IVF outcomes.
• To determine if additional embryonic micromanipulation impacts live birth rates and clinical pregnancy.

Main Methods:

• Retrospective cohort study of 2,973 patients undergoing IVF with single embryo transfer and trophectoderm biopsy for PGT-A.
• Patients were categorized into three groups based on the number of biopsy and cryopreservation cycles.
• Primary outcome was live birth; secondary outcomes included clinical pregnancy and miscarriage rates.

Main Results:

• The group undergoing one biopsy and two cryopreservation cycles showed significantly lower live birth rates (aRR 0.57) and clinical pregnancy rates (aRR 0.67) compared to the group with one biopsy and one cryopreservation cycle.
• Miscarriage rates were comparable between these two groups.

Conclusions:

• Multiple cryopreservation-warming cycles, particularly when combined with blastocyst biopsy, negatively impact IVF success.
• Clinicians should exercise caution when counseling patients regarding potential diminishing returns of PGT-A due to repeated embryonic micromanipulation.
• Further research is needed to optimize protocols for embryo handling during PGT-A cycles.