Corpus Luteum Function and Cardiovascular Adaptation in a Natural MOCK Cycle. (CLEAR)
9 juin 2026 mis à jour par: 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.
Aperçu de l'étude
Statut
Pas encore de recrutement
Les conditions
Type d'étude
Observationnel
Inscription (Estimé)
118
Contacts et emplacements
Cette section fournit les coordonnées de ceux qui mènent l'étude et des informations sur le lieu où cette étude est menée.
Coordonnées de l'étude
- Nom: Caroline Roelens
- Numéro de téléphone: 0032 2 477 9887
- E-mail: caroline.roelens@uzbrussel.be
Lieux d'étude
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-
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Jette, Belgique, 1090
- UZ Brussel
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Contact:
- Caroline Roelens
- Numéro de téléphone: 0032 2 477 9887
- E-mail: caroline.roelens@uzbrussel.be
-
-
Critères de participation
Les chercheurs recherchent des personnes qui correspondent à une certaine description, appelée critères d'éligibilité. Certains exemples de ces critères sont l'état de santé général d'une personne ou des traitements antérieurs.
Critère d'éligibilité
Âges éligibles pour étudier
- Adulte
Accepte les volontaires sains
Oui
Méthode d'échantillonnage
Échantillon de probabilité
Population étudiée
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.
La description
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).
Plan d'étude
Cette section fournit des détails sur le plan d'étude, y compris la façon dont l'étude est conçue et ce que l'étude mesure.
Comment l'étude est-elle conçue ?
Détails de conception
Cohortes et interventions
Groupe / Cohorte |
Intervention / Traitement |
|---|---|
|
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.
|
Que mesure l'étude ?
Principaux critères de jugement
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
|
The relationship between progesterone levels and different follicular sizes on day 7 post ovulation induction.
Délai: 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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Mesures de résultats secondaires
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
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Estradiol evolution throughout the cycle and its relation to luteal progesterone levels.
Délai: 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
Délai: 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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Collaborateurs et enquêteurs
C'est ici que vous trouverez les personnes et les organisations impliquées dans cette étude.
Parrainer
Dates d'enregistrement des études
Ces dates suivent la progression des dossiers d'étude et des soumissions de résultats sommaires à ClinicalTrials.gov. Les dossiers d'étude et les résultats rapportés sont examinés par la Bibliothèque nationale de médecine (NLM) pour s'assurer qu'ils répondent à des normes de contrôle de qualité spécifiques avant d'être publiés sur le site Web public.
Dates principales de l'étude
Début de l'étude (Estimé)
1 juillet 2026
Achèvement primaire (Estimé)
1 février 2028
Achèvement de l'étude (Estimé)
1 septembre 2028
Dates d'inscription aux études
Première soumission
9 juin 2026
Première soumission répondant aux critères de contrôle qualité
9 juin 2026
Première publication (Réel)
15 juin 2026
Mises à jour des dossiers d'étude
Dernière mise à jour publiée (Réel)
15 juin 2026
Dernière mise à jour soumise répondant aux critères de contrôle qualité
9 juin 2026
Dernière vérification
1 juin 2026
Plus d'information
Termes liés à cette étude
Termes MeSH pertinents supplémentaires
- Hormones
- Hormones, substituts hormonaux et antagonistes hormonaux
- Hormones peptidiques
- Peptides
- Acides aminés, peptides et protéines
- Protéines
- Techniques d'investigation
- Thérapeutique
- Manipulation des échantillons
- Techniques de laboratoire clinique
- Techniques et procédures de diagnostic
- Diagnostic
- Perforation
- Procédures chirurgicales, opératoires
- Techniques de reproduction, aidées
- Techniques de reproduction
- Gonadotrophines
- Hormones placentaires
- Protéines de grossesse
- Gonadotrophine chorionique
- Collection d'échantillons de sang
- Induction de l'ovulation
Autres numéros d'identification d'étude
- EC-2025-445
Informations sur les médicaments et les dispositifs, documents d'étude
Étudie un produit pharmaceutique réglementé par la FDA américaine
Non
Étudie un produit d'appareil réglementé par la FDA américaine
Non
Ces informations ont été extraites directement du site Web clinicaltrials.gov sans aucune modification. Si vous avez des demandes de modification, de suppression ou de mise à jour des détails de votre étude, veuillez contacter register@clinicaltrials.gov. Dès qu'un changement est mis en œuvre sur clinicaltrials.gov, il sera également mis à jour automatiquement sur notre site Web .