Immediate Versus Postponed Single Blastocyst Transfer in Programmed or Stimulated Cycle Frozen Embryo Transfer
1 other identifier
interventional
484
1 country
1
Brief Summary
The aim of this randomized controlled trial is to examine whether single blastocyst transfer in the first cycle after oocyte retrieval (immediate) is non-inferior to single blastocyst transfer in a subsequent cycle (postponed) in stimulated or programmed cycle frozen embryo transfer (FET). The primary outcome is live birth rate.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable
Started Feb 2024
Longer than P75 for not_applicable
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
Study Start
First participant enrolled
February 1, 2024
CompletedFirst Submitted
Initial submission to the registry
February 23, 2024
CompletedFirst Posted
Study publicly available on registry
March 12, 2024
CompletedPrimary Completion
Last participant's last visit for primary outcome
August 1, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
August 1, 2028
August 11, 2025
August 1, 2025
4.5 years
February 23, 2024
August 5, 2025
Conditions
Outcome Measures
Primary Outcomes (1)
Live birth rate
Live birth rate in immediate FET compared to postponed FET in women undergoing FET in a stimulated or programmed cycle.
One year follow up from positive pregnancy test.
Secondary Outcomes (13)
Live birth rate per blastocyst transfer
One year follow up from positive pregnancy test.
Ongoing pregnancy rate
At 7 or 8 weeks of gestation in case of pregnancy
Miscarriage rate
Until 22 weeks of gestation in women with positive pregnancy test
Cancelled cycle rate and reason for cancelled cycles
Will be assessed through study participation dependent on the participants cycle up to 50 days
Endocrinology of the luteal phase
Through each participants cycle, will be dependent on participants cycle up to 50 days
- +8 more secondary outcomes
Study Arms (2)
Immediate FET in a stimulated or programmed cycle
EXPERIMENTALStimulated or programmed cycle FET is performed in the first cycle following failed fresh embryo transfer or freeze all.
Postponed FET in a stimulated or programmed cycle
NO INTERVENTIONStimulated or programmed cycle FET is performed at least one full menstrual, or one hormonal replacement treatment (HRT) cycle in case of oligo-anovulation, after the fresh embryo transfer or freeze-all cycle
Interventions
Patients will undergo FET in the cycle immediately following oocyte retrieval and a failed fresh embryo transfer or freeze all.
Eligibility Criteria
You may qualify if:
- Eligible for FET in a programmed- or stimulated cycle immediately following a fresh embryo transfer or freeze all cycle
- Oligo-anovulatory women (cycle length \> 35 days)
- Ovulatory women (cycle length 21-35 days)
- At least one vitrified day 5 or 6 blastocyst with Gardner score of ≥ 3BB at the day of vitrification
You may not qualify if:
- Uterine malformation
- Presence of hydrosalpinx, submucosal uterine myomas or uterine polyps
- Allergies or contraindication to standard fertility medication
- Male or female HIV or Hepatitis B or C
- Preimplantation genetic testing (PGT) in the fresh cycle
- Testicular sperm aspiration (TESA)
- Severe OHSS with hospital admission and ascites drainage during the fresh cycle
- Oocyte donation
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
Fertility Departmen, Rigshospitalet
Copenhagen, 2100, Denmark
Related Publications (1)
Colombo C, Johansen AS, Saupstad M, Bergenheim SJ, Dam TV, Wang NF, Oxlund-Mariegaard B, Lokkegaard E, Husth M, Lauritsen MP, Forman JL, Freiesleben NC, Nohr B, Lossl K, Pinborg A. Immediate versus postponed blastocyst transfer in stimulated or programmed frozen embryo transfer cycles - a protocol for a non-blinded randomised clinical trial. Dan Med J. 2025 Jul 22;72(8):A03250214. doi: 10.61409/A03250214.
PMID: 40747727DERIVED
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Prof. DMSc
Study Record Dates
First Submitted
February 23, 2024
First Posted
March 12, 2024
Study Start
February 1, 2024
Primary Completion (Estimated)
August 1, 2028
Study Completion (Estimated)
August 1, 2028
Last Updated
August 11, 2025
Record last verified: 2025-08
Data Sharing
- IPD Sharing
- Will share
- Shared Documents
- STUDY PROTOCOL
- Time Frame
- From 3 months after publication on the primary and secondary outcomes in this study.
In case of requests, the final data will be shared according to the ICJME guidelines. Sharing will only be done with parties presenting new research projects which have been approved by the steering committee of the research team. Any new project involving data collected in this trial must also be approved by Danish authorities. Expenses for data sharing will be covered by those requesting it. Data will not be shared with research groups conducting projects with the same aim, secondary aims and/or purposes as ours until three months after publication of the primary and secondary outcomes of this study.