When to Transfer Embryos if There Is Only 1 or 2?
Martin Stimpfel1, Nina Jancar1,2, Helena Ban-Frangez1,2
1Department of Human Reproduction, Division of Obstetrics and Gynecology, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia.
Life (Basel, Switzerland)
|February 25, 2023
Summary
Embryo transfer on day five may improve birth rates in in vitro fertilization (IVF) cycles with few embryos, particularly for women under 36. This finding suggests optimizing embryo transfer timing based on embryo availability and patient age.
Area of Science:
- Reproductive Medicine
- Embryology
- In Vitro Fertilization (IVF)
Background:
- Day five embryo transfer (e.g., blastocyst stage) is often preferred in IVF.
- Its benefit is uncertain when only one to two embryos are available per cycle.
Purpose of the Study:
- To evaluate the effectiveness of day three versus day five embryo transfer (ET) in IVF/ICSI cycles with limited embryo yield (one to two embryos).
Main Methods:
- Retrospective analysis of stimulated IVF/ICSI cycles from January 2004 to December 2018.
- Comparison of outcomes between day three and day five ET in patients with one to two embryos.
- Statistical analysis of patient demographics, treatment parameters, and birth rates.
Main Results:
- The day three ET group had older patients, higher gonadotropin doses, and fewer oocytes/embryos.
- Day five ET was associated with a significantly higher birth rate per ET (p=0.045).
- This benefit was more pronounced in patients under 36 years old.
Conclusions:
- Day five ET may be advantageous over day three ET in IVF/ICSI cycles yielding only one to two embryos.
- The potential benefit of day five ET appears primarily for patients under 36 years old.
