Immediate Versus Delayed FET Following a Stimulated IVF Cycle

Study Overview
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Brief Summary
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Information regarding the optimal timing for frozen-thawed embryo transfer (FET) following a stimulated in vitro fertilization (IVF) is lacking. One option is to perform FET in the first cycle following the stimulated IVF cycle, i.e. immediate transfer. Another option is to postpone FET for at least one menstrual cycle, i.e. delayed transfer. This randomized study aims to compare the ongoing pregnancy rate of immediate versus delayed FET following a stimulated IVF cycle.

Official Title
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A Randomized Trial Comparing the Effect of Immediate Versus Delayed Frozen-thawed Embryo Transfer Following a Stimulated IVF Cycle

Conditions
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Fertilization in Vitro, Embryo Transfer

Intervention / Treatment
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* Other: immediate frozen-thawed embryo transfer
* Other: delayed frozen-thawed embryo transfer


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women aged ≤43 years at the time of IVF/ICSI treatment Undergoing IVF with a standard stimulation At least one frozen embryo or blastocyst The first FET cycle following ovarian stimulation in IVF/ICSI Exclusion Criteria: Use of mild stimulation or natural cycle for IVF/ICSI treatment Severe ovarian hyperstimulation syndrome during IVF/ICSI treatment Preimplantation genetic diagnosis treatment Use of donor oocytes Presence of hydrosalpinx which is not surgically treated or endometrial polyp on scanning during ovarian stimulation

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 43 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: immediate group<br>the intervention: immediate frozen-thawed embryo transfer (FET) which means FET will be performed in the first cycle following the stimulated IVF cycle | Other: immediate frozen-thawed embryo transfer<br>* Frozen-thawed embryo transfer will be performed in the first cycle following the stimulated IVF cycle<br>|
| Other: delayed group<br>the intervention: delayed frozen-thawed embryo transfer (FET) which means FET will be performed at least in the second cycle following the stimulated IVF cycle | Other: delayed frozen-thawed embryo transfer<br>* Frozen-thawed embryo transfer will be performed at least in the second cycle following the stimulated IVF cycle<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ongoing pregnancy | viable pregnancy beyond gestation 12 weeks | viable pregnancy beyond gestation 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Positive hCG level | the result of serum β-hCG ≥10 mIU/mL. | A blood pregnancy test is performed 14 days after the FET | 
| clinical pregnancy | presence of intrauterine gestational sac on ultrasound | presence of intrauterine gestational sac on ultrasound at 6 weeks of pregnancy | 
| biochemical pregnancy: | positive blood pregnancy test not followed by clinical pregnancy | positive blood pregnancy test not followed by clinical pregnancy during 12 weeks gestation | 
| implantation rate | number of gestational sacs per embryo transferred | number of gestational sacs per embryo transferred during 4 weeks of pregnancy | 
| multiple pregnancy | more than one intrauterine sacs on scanning | multiple pregnancy beyond gestation 12 weeks | 
| ectopic pregnancy | pregnancy outside the uterine cavity | ectopic pregnancy during 12 weeks gestation | 
| miscarriage | the loss of a pregnancy before 22 weeks gestation | the loss of a pregnancy before 22 weeks gestation | 
| live birth rate | the rate of live births per cycle | a live birth after 22 weeks gestation | 
| birth weight | birth weight of the baby delivered | a live birth after 22 weeks gestation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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frozen-thawed embryo transfer, time interval