Corpus Luteum Function and Cardiovascular Adaptation in a Natural MOCK Cycle. (CLEAR)
9 juni 2026 bijgewerkt door: Noa Wauters, Universitair Ziekenhuis Brussel
In infertility treatment, embryos are created in vitro after eggs have been fertilised by sperm using in vitro fertilisation or intracytoplasmic sperm injection techniques.
These embryos, resulting from hormonal ovarian stimulation, can be transferred shortly after egg retrieval (fresh transfer) or frozen for later use.
Both natural menstrual cycles and artificial cycles (using hormones to mimic a normal cycle) can prepare the uterus for embryo transfer.
Patients with regular menstrual cycles often prefer the non-medicated approach.
However, these cycles offer less flexibility in timing because they rely on ovulation.
As the number of FET cycles increases worldwide, scientists are exploring the possibility of inducing ovulation in smaller follicles to increase the flexibility of natural cycles.
However, the safety for future pregnancies is unknown.
This study aims to better understand the function of the corpus luteum, the follicle remnant in the ovary after ovulation, by measuring several factors that change throughout the cycle due to substances produced by the corpus luteum.
The results of the study will have a direct impact on clinical practice by increasing the flexibility of frozen transfer cycles.
Studie Overzicht
Toestand
Nog niet aan het werven
Studietype
Observationeel
Inschrijving (Geschat)
118
Contacten en locaties
In dit gedeelte vindt u de contactgegevens van degenen die het onderzoek uitvoeren en informatie over waar dit onderzoek wordt uitgevoerd.
Studiecontact
- Naam: Caroline Roelens
- Telefoonnummer: 0032 2 477 9887
- E-mail: caroline.roelens@uzbrussel.be
Studie Locaties
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-
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Jette, België, 1090
- UZ Brussel
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Contact:
- Caroline Roelens
- Telefoonnummer: 0032 2 477 9887
- E-mail: caroline.roelens@uzbrussel.be
-
-
Deelname Criteria
Onderzoekers zoeken naar mensen die aan een bepaalde beschrijving voldoen, de zogenaamde geschiktheidscriteria. Enkele voorbeelden van deze criteria zijn iemands algemene gezondheidstoestand of eerdere behandelingen.
Geschiktheidscriteria
Leeftijden die in aanmerking komen voor studie
- Volwassen
Accepteert gezonde vrijwilligers
Ja
Bemonsteringsmethode
Kanssteekproef
Studie Bevolking
Our study population pertains to female patients and volunteers, of the age between 18 years old and 40 years old, with a regular menstrual cycle (25-35 days) and a normal BMI (18.5-35).
You are eligible if you have not used any form of hormonal contraception or copper IUD throughout the last 3 months, have not had an ovarian stimulation during this time period, and are not known with renal or cardiac disease, diabetes or hypertension.
Beschrijving
Inclusion Criteria:
- Age below 40 years
- Regular menstrual cycles (between 25-35 days)
- Normal BMI between 18.5 and 35
Exclusion Criteria:
- Underlying renal or cardiac disease
- Hypertension
- Diabetes mellitus
- Contraceptive use less than 3 months before MOCK cycle, including: IUD (hormonal and copper), hormonal patch, contraceptive pill (combination and mini), hormonal intravaginal ring, contraceptive implant, contraceptive injection.
- Ovarian stimulation during the previous three months
- History of recurrent pregnancy loss (defined as 2 or more previous pregnancy losses before 24 weeks gestation).
Studie plan
Dit gedeelte bevat details van het studieplan, inclusief hoe de studie is opgezet en wat de studie meet.
Hoe is de studie opgezet?
Ontwerpdetails
Cohorten en interventies
Groep / Cohort |
Interventie / Behandeling |
|---|---|
|
Follicle size 11mm
Patients with a follicle of 11mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
|
Follicle size 12 mm
Patients with a follicle of 12mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
|
Follicle size 13 mm
Patients with a follicle of 13mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
|
Follicle size 14 mm
Patients with a follicle of 14mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
|
Follicle size 15 mm
Patients with a follicle of 15mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
|
Follicle size 16 mm
Patients with a follicle of 16mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
|
Follicle size 17 mm
Patients with a follicle of 17mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
|
Follicle size 18 mm
Patients with a follicle of 18mm when measured through transvaginal ultrasound in 2D, at time of ovulation induction.
|
We will collect several blood samples:
A transvaginal ultrasound will be performed after day 8 of the cycle to evaluate a 2D measurement of the growing follicle, as well as a measurement of the endometrial thickness to evaluate readiness for ovulation induction.
The MAP will be measured at cycle day 7 and 7 days post-ovulation induction to follow cardiovascular adaptations.
When patient is deemed ready for ovulation based on follicle size, blood results and endometrium, she will be asked to inject Ovitrelle 250 micrograms to induce ovulation in a controlled and timed manner.
|
Wat meet het onderzoek?
Primaire uitkomstmaten
Uitkomstmaat |
Maatregel Beschrijving |
Tijdsspanne |
|---|---|---|
|
The relationship between progesterone levels and different follicular sizes on day 7 post ovulation induction.
Tijdsspanne: From the start of the menstrual cycle until 7 days after ovulation induction.
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Progesterone levels will be measured 7 days after ovulation induction to relate them to different follicular sizes.
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From the start of the menstrual cycle until 7 days after ovulation induction.
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Secundaire uitkomstmaten
Uitkomstmaat |
Maatregel Beschrijving |
Tijdsspanne |
|---|---|---|
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Estradiol evolution throughout the cycle and its relation to luteal progesterone levels.
Tijdsspanne: From the start of a menstrual cycle until 7 days post-ovulation induction.
|
We will measure the estradiol on different moments throught the menstural cycle, and see how these levels correspond to later (luteal) progesterone levels.
|
From the start of a menstrual cycle until 7 days post-ovulation induction.
|
|
Indirect factors reflecting cardiovascular and renal adaptation in the luteal phase
Tijdsspanne: From the start of the menstrual cycle until 7 days after ovulation induction.
|
We will measure these factors (MAP, progesterone, estradiol, serum sodium, chloride, carbon dioxide and osmolality, prolactin, direct renin, plasma aldosterone, NT-proBNP, relaxin-2 and VEGF) at day 8 of the cycle, as well as 7 days after ovulation-induction.
All these factors form a reflection of the body's cardiovascular and renal adaptation, and will be studied to estimate these adaptation at different follicular sizes.
|
From the start of the menstrual cycle until 7 days after ovulation induction.
|
Medewerkers en onderzoekers
Hier vindt u mensen en organisaties die betrokken zijn bij dit onderzoek.
Sponsor
Studie record data
Deze datums volgen de voortgang van het onderzoeksdossier en de samenvatting van de ingediende resultaten bij ClinicalTrials.gov. Studieverslagen en gerapporteerde resultaten worden beoordeeld door de National Library of Medicine (NLM) om er zeker van te zijn dat ze voldoen aan specifieke kwaliteitscontrolenormen voordat ze op de openbare website worden geplaatst.
Bestudeer belangrijke data
Studie start (Geschat)
1 juli 2026
Primaire voltooiing (Geschat)
1 februari 2028
Studie voltooiing (Geschat)
1 september 2028
Studieregistratiedata
Eerst ingediend
9 juni 2026
Eerst ingediend dat voldeed aan de QC-criteria
9 juni 2026
Eerst geplaatst (Werkelijk)
15 juni 2026
Updates van studierecords
Laatste update geplaatst (Werkelijk)
15 juni 2026
Laatste update ingediend die voldeed aan QC-criteria
9 juni 2026
Laatst geverifieerd
1 juni 2026
Meer informatie
Termen gerelateerd aan deze studie
Aanvullende relevante MeSH-voorwaarden
- Hormonen
- Hormonen, hormoonvervangers en hormoonantagonisten
- Peptide hormonen
- Peptiden
- Aminozuren, peptiden en eiwitten
- Eiwitten
- Onderzoekstechnieken
- Therapeutica
- Exemplaarbehandeling
- Klinische laboratoriumtechnieken
- Diagnostische technieken en procedures
- Diagnose
- Buren
- Chirurgische procedures, operatief
- Reproductieve technieken, geholpen
- Reproductieve technieken
- Gonadotropins
- Placentale hormonen
- Zwangerschapseiwitten
- Choriongonadotrofine
- Bloedspecimenverzameling
- Ovulatie -inductie
Andere studie-ID-nummers
- EC-2025-445
Informatie over medicijnen en apparaten, studiedocumenten
Bestudeert een door de Amerikaanse FDA gereguleerd geneesmiddel
Nee
Bestudeert een door de Amerikaanse FDA gereguleerd apparaatproduct
Nee
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