Corpus Luteum Function and Cardiovascular Adaptation in a Natural MOCK Cycle. (CLEAR)
9. juni 2026 opdateret af: 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.
Studieoversigt
Status
Ikke rekrutterer endnu
Betingelser
Undersøgelsestype
Observationel
Tilmelding (Anslået)
118
Kontakter og lokationer
Dette afsnit indeholder kontaktoplysninger for dem, der udfører undersøgelsen, og oplysninger om, hvor denne undersøgelse udføres.
Studiekontakt
- Navn: Caroline Roelens
- Telefonnummer: 0032 2 477 9887
- E-mail: caroline.roelens@uzbrussel.be
Studiesteder
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-
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Jette, Belgien, 1090
- UZ Brussel
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Kontakt:
- Caroline Roelens
- Telefonnummer: 0032 2 477 9887
- E-mail: caroline.roelens@uzbrussel.be
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-
Deltagelseskriterier
Forskere leder efter personer, der passer til en bestemt beskrivelse, kaldet berettigelseskriterier. Nogle eksempler på disse kriterier er en persons generelle helbredstilstand eller tidligere behandlinger.
Berettigelseskriterier
Aldre berettiget til at studere
- Voksen
Tager imod sunde frivillige
Ja
Prøveudtagningsmetode
Sandsynlighedsprøve
Studiebefolkning
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.
Beskrivelse
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).
Studieplan
Dette afsnit indeholder detaljer om studieplanen, herunder hvordan undersøgelsen er designet, og hvad undersøgelsen måler.
Hvordan er undersøgelsen tilrettelagt?
Design detaljer
Kohorter og interventioner
Gruppe / kohorte |
Intervention / Behandling |
|---|---|
|
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.
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Hvad måler undersøgelsen?
Primære resultatmål
Resultatmål |
Foranstaltningsbeskrivelse |
Tidsramme |
|---|---|---|
|
The relationship between progesterone levels and different follicular sizes on day 7 post ovulation induction.
Tidsramme: 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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Sekundære resultatmål
Resultatmål |
Foranstaltningsbeskrivelse |
Tidsramme |
|---|---|---|
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Estradiol evolution throughout the cycle and its relation to luteal progesterone levels.
Tidsramme: From the start of a menstrual cycle until 7 days post-ovulation induction.
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We will measure the estradiol on different moments throught the menstural cycle, and see how these levels correspond to later (luteal) progesterone levels.
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From the start of a menstrual cycle until 7 days post-ovulation induction.
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Indirect factors reflecting cardiovascular and renal adaptation in the luteal phase
Tidsramme: From the start of the menstrual cycle until 7 days after ovulation induction.
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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.
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From the start of the menstrual cycle until 7 days after ovulation induction.
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Samarbejdspartnere og efterforskere
Det er her, du vil finde personer og organisationer, der er involveret i denne undersøgelse.
Sponsor
Datoer for undersøgelser
Disse datoer sporer fremskridtene for indsendelser af undersøgelsesrekord og resumeresultater til ClinicalTrials.gov. Studieregistreringer og rapporterede resultater gennemgås af National Library of Medicine (NLM) for at sikre, at de opfylder specifikke kvalitetskontrolstandarder, før de offentliggøres på den offentlige hjemmeside.
Studer store datoer
Studiestart (Anslået)
1. juli 2026
Primær færdiggørelse (Anslået)
1. februar 2028
Studieafslutning (Anslået)
1. september 2028
Datoer for studieregistrering
Først indsendt
9. juni 2026
Først indsendt, der opfyldte QC-kriterier
9. juni 2026
Først opslået (Faktiske)
15. juni 2026
Opdateringer af undersøgelsesjournaler
Sidste opdatering sendt (Faktiske)
15. juni 2026
Sidste opdatering indsendt, der opfyldte kvalitetskontrolkriterier
9. juni 2026
Sidst verificeret
1. juni 2026
Mere information
Begreber relateret til denne undersøgelse
Yderligere relevante MeSH-vilkår
- Hormoner
- Hormoner, hormonsubstitutter og hormonantagonister
- Peptidhormoner
- Peptider
- Aminosyrer, peptider og proteiner
- Proteiner
- Undersøgelsesteknikker
- Terapeutik
- Håndtering af eksemplar
- Kliniske laboratorieteknikker
- Diagnostiske teknikker og procedurer
- Diagnose
- Punkteringer
- Kirurgiske procedurer, operative
- Reproduktionsteknikker, assisteret
- Reproduktionsteknikker
- Gonadotropiner
- Placentale hormoner
- Graviditetsproteiner
- Choriongonadotropin
- Blodprøveopsamling
- Ægløsningsinduktion
Andre undersøgelses-id-numre
- EC-2025-445
Lægemiddel- og udstyrsoplysninger, undersøgelsesdokumenter
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