Natural Frozen Embryo Transfer (FET) vs Substituted Frozen Embryo Transfer (FET)

Active, not recruiting

• Conditions: Fertility Disorders
• Interventions: Other: Frozen embryo transfer

• Registration Number: NCT06053827
• Lead Sponsor: Clinique Ovo

Brief Summary

In frozen embryo transfer substituted cycles, patients are treated with progesterone and estrogen in an attempt to mimic the natural cycle and a transfer is planned whenever the endometrium is ready. In contrast, in frozen embryo transfer natural cycle patients are not taking any hormones, only triggered with hCG (human chorionic gonadotropin) when a dominant follicle is ready or they wait for the disappearance of the dominant follicle to plan the transfer date. Some doctors and centres shift towards using the substituted protocol in an attempt to make scheduling easier with less frequent ultrasounds.

This study will aim to compare clinical and biochemical pregnancy rates in patients who underwent frozen embryo transfers in natural cycles vs substituted cycles at the centre.

Detailed Description

Not available

Study Timeline

• Study Start: 2023-09-19
• Study First Submitted: 2023-09-19
• Study First Submitted QC: 2023-09-19
• Study First Posted: 2023-09-26
• Primary Completion: 2023-11-30
• Status Verified: 2024-01
• Last Update Submitted: 2024-01-10
• Last Update Posted: 2024-01-12
• Study Completion: 2024-09-30

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: Female
• Target Recruitment: 500

Inclusion Criteria

• Age < 40 years old
• Women having undergone either a frozen embryo transfer in natural cycle or substituted cycle
• IVF and FET cycles done at Clinique OVO

Exclusion Criteria

• egg or embryo recipient
• History of recurrent miscarriages, defined as ≥ 3 consecutive losses
• Patients that needed Viagra, Plasma-Rich Platelet (PRP) or other modalities to improve their endometrial thickness
• Uterine abnormalities
• Abnormal hormonal profiles
• FET Stimulated cycles
• History of recurrent implantation failure defined as failed ≥ 2 euploid embryos transfer or ≥ 3 blastocysts

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Frozen embryo transfer substituted cycle	Frozen embryo transfer	In a substituted cycle, estrogen and progesterone are given and a transfer is planned when the endometrium is ready
Frozen embryo transfer natural cycle	Frozen embryo transfer	In a natural cycle no hormones are given and a transfer is planned when there is a dominant follicle apparent at the ultrasound

Primary Outcome Measures

Name	Time	Method
Evaluate the clinical pregnancy rate of embryo transfer in natural vs substituted cycles	6 to 8 weeks after Frozen Embryo Transfer	clinical pregnancy is the presence of fetal heartbeat at the viability ultrasound

Trial Locations

Locations (1)

Clinique Ovo; 🇨🇦 Montréal, Quebec, Canada