Optimal Timing of Euploid Day 6 Blastocyst Transfer in Frozen HRT Cycles, Day 6 or Day 7 of Progesterone Administration.

June 22, 2026 updated by: ART Fertility Clinics LLC

Optimal Timing of Euploid Day 6 Blastocyst (Blastocyst Which Was Biopsied on Day 6 After Fertilization) Transfer in Frozen Hormonal Replacement Therapy Cycles: Day 6 or Day 7 of Progesterone Administration?

The goal of this study is to compare the difference in clinical pregnancy, miscarriage and livebirth rate between day 6 euploid blastocyst transfer on the 6th and the 7th day of progesterone exposure in Hormonal Replacement Therapy (HRT) FET cycles. This prospective & randomized study will only include euploid day 6 blastocysts. This will be the first prospective study of euploid day 6 blastocysts thereby excluding aneuploidy as a cause of miscarriage and implantation failure. The point of randomization will occur on the day of progesterone commencement.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Suspended

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Traditionally the duration of progesterone exposure before embryo transfer has been considered equal for day 5 and day 6 embryos but this may not be the case and warrants further study. The optimal preparation of the endometrium in frozen embryo transfer (FET) cycles is yet to be determined. Synchronization between the embryonic stage and the endometrial window of implantation (WOI) is crucial and progesterone plays a critical role in the WOI (1). Data on the optimal route of administration, the dose and duration of progesterone supplementation before blastocyst transfer are inconsistent (2,3). In view of the current lack of evidence, this study will be of importance.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
316

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United Arab Emirates
      • Dubai, United Arab Emirates
        • ART Fertility Clinics Dubai
    • Abu Dhabi Emirate
      • Abu Dhabi, Abu Dhabi Emirate, United Arab Emirates, 60202
        • ART Fertility Clinics LLC

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Women aged 18 years to 43 years.
  • Having at least 1 euploid cryopreserved day 6 blastocyst of at least Grade BB quality.
  • Endometrial trilaminar appearance on the day of progesterone start

Exclusion Criteria:

  • Uterine abnormality
  • Hydrosalpinx
  • Asherman syndrome
  • Any known contraindications or allergy to oral estradiol or progesterone.

  • Intention to treat : exclusion factors :

    1. Spontaneous ovulation HRT cycle
    2. Discontinuation of HRT medication

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Other: Group A
Embryo transfer is scheduled on the 6th full day of progesterone administration, following the initial commencement of progesterone (120 hours)
Diagnostic test: Transvaginal ultrasound
Transvaginal ultrasound throughout the HRT cycle to not only monitor endometrial development but to also exclude the presence of an ovarian dominant follicle
Diagnostic test: Serum LH, E2, P4
In conjunction with ultrasound monitoring, participants will undergo serial measurements of serum Luteinizing Hormone (LH), Estradiol (E2) and Progesterone (P4) levels
Drug: Estradiol Valerate 2 MG

Participants will commence estradiol valerate 4 mg ( 2 x 2 mg) on day 2 / day 3 of menses.

Estradiol will be increased to 6 mg on day 2 of estrogen treatment, and continued at a daily dose of 6 mg (3 tablets daily)

Other Names:
  • Estradiol Valerate
Drug: Progesterone 100 Mg Vaginal Insert
The initial progesterone dose of 100 mg will be commenced at 13hrs and repeated at 21hrs considered day 1 (vaginal suppository) when an optimal endometrial thickness for each participant has been achieved with a trilaminar appearance. The following day (day 2) progesterone administration will be increased to 100 mg vaginally three times daily
Other Names:
  • Progesterone 100 mg
Diagnostic test: Serum P4 day of ET
On the day of embryo transfer (ET), a blood test is taken to measure serum P4
Procedure: Embryo transfer
Procedure in which embryo is transferred into the uterus
Other Names:
  • ET
Other: Group B
Embryo Transfer is scheduled on the 7th full day of progesterone administration, following the initial commencement of progesterone (144 hours)
Diagnostic test: Transvaginal ultrasound
Transvaginal ultrasound throughout the HRT cycle to not only monitor endometrial development but to also exclude the presence of an ovarian dominant follicle
Diagnostic test: Serum LH, E2, P4
In conjunction with ultrasound monitoring, participants will undergo serial measurements of serum Luteinizing Hormone (LH), Estradiol (E2) and Progesterone (P4) levels
Drug: Estradiol Valerate 2 MG

Participants will commence estradiol valerate 4 mg ( 2 x 2 mg) on day 2 / day 3 of menses.

Estradiol will be increased to 6 mg on day 2 of estrogen treatment, and continued at a daily dose of 6 mg (3 tablets daily)

Other Names:
  • Estradiol Valerate
Drug: Progesterone 100 Mg Vaginal Insert
The initial progesterone dose of 100 mg will be commenced at 13hrs and repeated at 21hrs considered day 1 (vaginal suppository) when an optimal endometrial thickness for each participant has been achieved with a trilaminar appearance. The following day (day 2) progesterone administration will be increased to 100 mg vaginally three times daily
Other Names:
  • Progesterone 100 mg
Diagnostic test: Serum P4 day of ET
On the day of embryo transfer (ET), a blood test is taken to measure serum P4
Procedure: Embryo transfer
Procedure in which embryo is transferred into the uterus
Other Names:
  • ET

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Livebirth rate (LBR)
Time Frame: 41 weeks
Defined as the delivery of a live infant born after 24 completed weeks of gestation
41 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Biochemical pregnancy rate
Time Frame: 5 weeks
Positive hCG, but at 5 gestational weeks no ultrasonographic visible gestational sac seen but without a further development into a clinical pregnancy)
5 weeks
Clinical pregnancy rate
Time Frame: 5 weeks
Ultrasonographic sac visible at 5 gestational weeks
5 weeks
Ongoing pregnancy rate after 12 weeks
Time Frame: 13 weeks
Viable pregnancy with a gestational age of more than 12 weeks
13 weeks
Miscarriage rate
Time Frame: 24 weeks
Spontaneous loss of a clinical pregnancy before 24 completed weeks of gestation
24 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
ART Fertility Clinics LLC

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Carol Coughlan, PhD, ART Fertility Clinics LLC

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
September 22, 2023

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 30, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 30, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
July 25, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 4, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
August 7, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
June 25, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 22, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2306-ABU-013-CC

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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