AzTrials
AzTrials

InfertilityPhase 1NCT05980091

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

A Phase 1 study testing Transvaginal ultrasound, Serum LH, E2, P4 and Estradiol Valerate 2 MG in people with Infertility and Fertility Issues, run by ART Fertility Clinics LLC at 2 sites in United Arab Emirates.

Suspended

Paused. Enrolment is on hold for now and may resume.

Official record
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Trial summary

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. Read more about this study

Who is it for?
Ages 18 to 43 years, women onlyHealthy volunteers can take part
Conditions the study is for
Infertility, Fertility Issues, Infertility, Female
What is being tested?
Transvaginal ultrasound, Serum LH, E2, P4 and Estradiol Valerate 2 MG
Could I receive a placebo?
No, everyone receives an active treatment
How many people
316 participants
Where
2 sitesUnited Arab Emirates
Study dates
22 Sep 2023to 30 Dec 2026
Phase
Phase 1
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 43 years
  • Women only
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • 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

Who cannot join

  • Uterine abnormality
  • Hydrosalpinx
  • Asherman syndrome
  • Any known contraindications or allergy to oral estradiol or progesterone.
  • Intention to treat : exclusion factors :
  • Spontaneous ovulation HRT cycle
  • Discontinuation of HRT medication

Trial locations and contacts

2 sites in 1 country.

United Arab Emirates2 sites

  • ART Fertility Clinics LLC

    Abu Dhabi, Abu Dhabi Emirate, 60202

  • ART Fertility Clinics Dubai

    Dubai

Other trials in United Arab Emirates

About this study

Official title: 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.

Read the 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.

Being tested
Transvaginal ultrasound, Serum LH, E2, P4, Estradiol Valerate 2 MG, Progesterone 100 Mg Vaginal Insert, Serum P4 day of ET
Keywords
Implantation, Infertility, Blastocyst, HRT, Progesterone
Medical subject headings
Infertility, Infertility, Female

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Transvaginal ultrasoundDiagnostic test

    Transvaginal ultrasound throughout the HRT cycle to not only monitor endometrial development but to also exclude the presence of an ovarian dominant follicle

  • Serum LH, E2, P4Diagnostic test

    In conjunction with ultrasound monitoring, participants will undergo serial measurements of serum Luteinizing Hormone (LH), Estradiol (E2) and Progesterone (P4) levels

  • Estradiol Valerate 2 MGDrug

    Also called Estradiol Valerate

    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)

  • Progesterone 100 Mg Vaginal InsertDrug

    Also called Progesterone 100 mg

    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

  • Serum P4 day of ETDiagnostic test

    On the day of embryo transfer (ET), a blood test is taken to measure serum P4

  • Embryo transferProcedure or surgery

    Also called ET

    Procedure in which embryo is transferred into the uterus

Study groups in NCT05980091
Study groupRoleWhat they receive
Group AOtherEmbryo transfer is scheduled on the 6th full day of progesterone administration, following the initial commencement of progesterone (120 hours)
Receives: Diagnostic Test: Transvaginal ultrasound; Diagnostic Test: Serum LH, E2, P4; Drug: Estradiol Valerate 2 MG; Drug: Progesterone 100 Mg Vaginal Insert; Diagnostic Test: Serum P4 day of ET; Procedure: Embryo transfer
Group BOtherEmbryo Transfer is scheduled on the 7th full day of progesterone administration, following the initial commencement of progesterone (144 hours)
Receives: Diagnostic Test: Transvaginal ultrasound; Diagnostic Test: Serum LH, E2, P4; Drug: Estradiol Valerate 2 MG; Drug: Progesterone 100 Mg Vaginal Insert; Diagnostic Test: Serum P4 day of ET; Procedure: Embryo transfer

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Livebirth rate (LBR)

    Defined as the delivery of a live infant born after 24 completed weeks of gestation

    Measured: 41 weeks

Secondary outcomes (4)

  1. Biochemical pregnancy rate

    Positive hCG, but at 5 gestational weeks no ultrasonographic visible gestational sac seen but without a further development into a clinical pregnancy)

    Measured: 5 weeks

  2. Clinical pregnancy rate

    Ultrasonographic sac visible at 5 gestational weeks

    Measured: 5 weeks

  3. Ongoing pregnancy rate after 12 weeks

    Viable pregnancy with a gestational age of more than 12 weeks

    Measured: 13 weeks

  4. Miscarriage rate

    Spontaneous loss of a clinical pregnancy before 24 completed weeks of gestation

    Measured: 24 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted7 Aug 2023
  2. Study start22 Sep 2023
  3. Primary completion30 Dec 2026 (estimated)
  4. Study completion30 Dec 2026 (estimated)

Why it stopped: Difficulty of enrolling and recruiting patients

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 1
Primary purpose
Basic science
Allocation
Randomised
Intervention model
Parallel groups
Masking
None (open label)
Enrolment
316 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05980091
Sponsor's protocol ID
2306-ABU-013-CC
Status last verified
Jun 2026
First submitted
25 Jul 2023
Last updated
25 Jun 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Franasiak JM, Ruiz-Alonso M, Scott RT, Simon C. Both slowly developing embryos and a variable pace of luteal endometrial progression may conspire to prevent normal birth in spite of a capable embryo. Fertil Steril. 2016 Apr;105(4):861-6. doi: 10.1016/j.fertnstert.2016.02.030.

    PubMed 26940791

  • Nawroth F, Ludwig M. What is the 'ideal' duration of progesterone supplementation before the transfer of cryopreserved-thawed embryos in estrogen/progesterone replacement protocols? Hum Reprod. 2005 May;20(5):1127-34. doi: 10.1093/humrep/deh762. Epub 2005 Feb 3.

    PubMed 15695314

  • van de Vijver A, Drakopoulos P, Polyzos NP, Van Landuyt L, Mackens S, Santos-Ribeiro S, Vloeberghs V, Tournaye H, Blockeel C. Vitrified-warmed blastocyst transfer on the 5th or 7th day of progesterone supplementation in an artificial cycle: a randomised controlled trial. Gynecol Endocrinol. 2017 Oct;33(10):783-786. doi: 10.1080/09513590.2017.1318376. Epub 2017 Apr 26.

    PubMed 28443690

  • Zegers-Hochschild F, Adamson GD, Dyer S, Racowsky C, de Mouzon J, Sokol R, Rienzi L, Sunde A, Schmidt L, Cooke ID, Simpson JL, van der Poel S. The International Glossary on Infertility and Fertility Care, 2017. Fertil Steril. 2017 Sep;108(3):393-406. doi: 10.1016/j.fertnstert.2017.06.005. Epub 2017 Jul 29.

    PubMed 28760517

  • Roelens C, Santos-Ribeiro S, Becu L, Mackens S, Van Landuyt L, Racca A, De Vos M, van de Vijver A, Tournaye H, Blockeel C. Frozen-warmed blastocyst transfer after 6 or 7 days of progesterone administration: impact on live birth rate in hormone replacement therapy cycles. Fertil Steril. 2020 Jul;114(1):125-132. doi: 10.1016/j.fertnstert.2020.03.017. Epub 2020 Jun 16.

    PubMed 32553469

  • Bourdon M, Pocate-Cheriet K, Finet de Bantel A, Grzegorczyk-Martin V, Amar Hoffet A, Arbo E, Poulain M, Santulli P. Day 5 versus Day 6 blastocyst transfers: a systematic review and meta-analysis of clinical outcomes. Hum Reprod. 2019 Oct 2;34(10):1948-1964. doi: 10.1093/humrep/dez163.

    PubMed 31644803

  • Shapiro BS, Daneshmand ST, Garner FC, Aguirre M, Hudson C. Clinical rationale for cryopreservation of entire embryo cohorts in lieu of fresh transfer. Fertil Steril. 2014 Jul;102(1):3-9. doi: 10.1016/j.fertnstert.2014.04.018. Epub 2014 May 17.

    PubMed 24842675

Questions about this trial

What is this clinical trial studying?

A Phase 1 study testing Transvaginal ultrasound, Serum LH, E2, P4 and Estradiol Valerate 2 MG in people with Infertility and Fertility Issues, run by ART Fertility Clinics LLC at 2 sites in United Arab Emirates.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: paused, as of the sponsor's last update on 25 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 2 sites in United Arab Emirates. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Results are not available in the source record.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Livebirth rate (LBR) (time frame: 41 weeks). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05980091, which also lists 7 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 25 Jun 2026.

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