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[Frozen embryo transfer protocol: does spontaneous cycle give good results?]
D El Bahja1, P Hertz, T Schweitzer
1Centre d'assistance médicale à la procréation, hôpital maternité de Metz, 8, rue des Récollets, 57042 Metz cedex 1, France.
Gynecologie, Obstetrique & Fertilite
|February 21, 2012
Summary
Frozen embryo transfers in spontaneous cycles resulted in higher pregnancy and delivery rates compared to substituted or stimulated cycles. This suggests natural cycles are optimal for normo-ovulating patients undergoing frozen embryo transfer.
Area of Science:
- Reproductive Endocrinology
- In Vitro Fertilization
- Embryo Transfer Protocols
Context:
- Frozen embryo transfer (FET) is crucial for optimizing pregnancy rates per retrieval.
- In France, stimulated cycles account for 60% of FET procedures.
- Optimal endometrial preparation for FET remains debated.
Purpose:
- To evaluate and compare the outcomes of frozen embryo transfers performed in spontaneous, substituted, and stimulated cycles.
- To determine the most effective endometrial preparation method for FET.
Summary:
- This retrospective study analyzed 333 patients undergoing FET, comparing spontaneous (n=132), substituted (n=24), and stimulated (n=177) cycles.
- Pregnancy rates were significantly higher in spontaneous cycles (20.49%) versus substituted (13.04%) and stimulated (11.32%) cycles (P=0.0348).
- Delivery rates also showed a similar trend, being significantly higher in spontaneous cycles (13.93%) compared to substituted (8.7%) and stimulated (6.29%) cycles (P=0.0314).
Impact:
- Findings support the use of spontaneous cycles for FET in normo-ovulating patients.
- Natural cycles offer a cost-effective and less burdensome alternative with comparable or superior success rates.
- This research provides evidence to guide clinical decisions in assisted reproductive technology.
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