Predictive factors for live birth in cryopreservation single embryo transfer cycles

Area of Science:

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

Background:

• IVF cryopreservation cycles demonstrate lower success rates compared to fresh cycles.
• Identifying predictors for live birth rate in cryopreservation single embryo transfers (SET) is crucial for improving outcomes.
• Understanding prognostic factors aids in decisions regarding single vs. double embryo transfer in frozen embryo transfer (FET) cycles.

Purpose of the Study:

• To identify maternal and embryonic variables that independently predict live birth rate in cryopreservation SET.
• To analyze the impact of specific factors on pregnancy and live birth rates following frozen embryo transfer.
• To assess the predictive value of identified variables in estimating prognosis for cryopreservation cycles.

Main Methods:

• Retrospective analysis of 622 cryopreservation SET from 371 patients.
• Logistic regression analysis of maternal and embryonic variables.
• Comparison of IVF with intracytoplasmic sperm injection (ICSI) as fertilization methods.

Main Results:

• Overall pregnancy and live birth rates were 22% and 16%, respectively.
• Positive predictors for live birth included blastomere survival rate, number of previous fresh cycles, and IVF fertilization method (vs. ICSI).
• Thawing multiple embryos for one transfer negatively impacted pregnancy rates but not live birth rates.

Conclusions:

• Blastomere survival, prior fresh cycles, and fertilization method are independent predictors of live birth in cryopreservation SET.
• While some predictors are identified, their overall predictive value for live birth and pregnancy is low.
• Knowledge of these predictors can inform prognostic estimations and transfer strategy decisions in frozen embryo transfer cycles.