Corpus Luteum Function and Cardiovascular Adaptation in a Natural MOCK Cycle. (CLEAR)
9 de junio de 2026 actualizado por: 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.
Descripción general del estudio
Estado
Aún no reclutando
Condiciones
Tipo de estudio
De observación
Inscripción (Estimado)
118
Contactos y Ubicaciones
Esta sección proporciona los datos de contacto de quienes realizan el estudio e información sobre dónde se lleva a cabo este estudio.
Estudio Contacto
- Nombre: Caroline Roelens
- Número de teléfono: 0032 2 477 9887
- Correo electrónico: caroline.roelens@uzbrussel.be
Ubicaciones de estudio
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Jette, Bélgica, 1090
- UZ Brussel
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Contacto:
- Caroline Roelens
- Número de teléfono: 0032 2 477 9887
- Correo electrónico: caroline.roelens@uzbrussel.be
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Criterios de participación
Los investigadores buscan personas que se ajusten a una determinada descripción, denominada criterio de elegibilidad. Algunos ejemplos de estos criterios son el estado de salud general de una persona o tratamientos previos.
Criterio de elegibilidad
Edades elegibles para estudiar
- Adulto
Acepta Voluntarios Saludables
Sí
Método de muestreo
Muestra de probabilidad
Población de estudio
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.
Descripción
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 de estudios
Esta sección proporciona detalles del plan de estudio, incluido cómo está diseñado el estudio y qué mide el estudio.
¿Cómo está diseñado el estudio?
Detalles de diseño
Cohortes e Intervenciones
Grupo / Cohorte |
Intervención / Tratamiento |
|---|---|
|
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.
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|
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.
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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.
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|
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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¿Qué mide el estudio?
Medidas de resultado primarias
Medida de resultado |
Medida Descripción |
Periodo de tiempo |
|---|---|---|
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The relationship between progesterone levels and different follicular sizes on day 7 post ovulation induction.
Periodo de tiempo: 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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Medidas de resultado secundarias
Medida de resultado |
Medida Descripción |
Periodo de tiempo |
|---|---|---|
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Estradiol evolution throughout the cycle and its relation to luteal progesterone levels.
Periodo de tiempo: 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
Periodo de tiempo: 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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Colaboradores e Investigadores
Aquí es donde encontrará personas y organizaciones involucradas en este estudio.
Patrocinador
Fechas de registro del estudio
Estas fechas rastrean el progreso del registro del estudio y los envíos de resultados resumidos a ClinicalTrials.gov. Los registros del estudio y los resultados informados son revisados por la Biblioteca Nacional de Medicina (NLM) para asegurarse de que cumplan con los estándares de control de calidad específicos antes de publicarlos en el sitio web público.
Fechas importantes del estudio
Inicio del estudio (Estimado)
1 de julio de 2026
Finalización primaria (Estimado)
1 de febrero de 2028
Finalización del estudio (Estimado)
1 de septiembre de 2028
Fechas de registro del estudio
Enviado por primera vez
9 de junio de 2026
Primero enviado que cumplió con los criterios de control de calidad
9 de junio de 2026
Publicado por primera vez (Actual)
15 de junio de 2026
Actualizaciones de registros de estudio
Última actualización publicada (Actual)
15 de junio de 2026
Última actualización enviada que cumplió con los criterios de control de calidad
9 de junio de 2026
Última verificación
1 de junio de 2026
Más información
Términos relacionados con este estudio
Términos MeSH relevantes adicionales
- Hormonas
- Hormonas, sustitutos hormonales y antagonistas hormonales
- Hormonas peptídicas
- Péptidos
- Aminoácidos, péptidos y proteínas
- Proteínas
- Técnicas de investigación
- Terapéutica
- Manejo de muestras
- Técnicas de laboratorio clínico
- Técnicas y procedimientos de diagnóstico
- Diagnóstico
- Puntas
- Procedimientos quirúrgicos, operativo
- Técnicas reproductivas, asistido
- Técnicas reproductivas
- Gonadotropinas
- Hormonas placentarias
- Proteínas del embarazo
- Gonadotropina coriónica
- Recolección de muestras de sangre
- Inducción de ovulación
Otros números de identificación del estudio
- EC-2025-445
Información sobre medicamentos y dispositivos, documentos del estudio
Estudia un producto farmacéutico regulado por la FDA de EE. UU.
No
Estudia un producto de dispositivo regulado por la FDA de EE. UU.
No
Esta información se obtuvo directamente del sitio web clinicaltrials.gov sin cambios. Si tiene alguna solicitud para cambiar, eliminar o actualizar los detalles de su estudio, comuníquese con register@clinicaltrials.gov. Tan pronto como se implemente un cambio en clinicaltrials.gov, también se actualizará automáticamente en nuestro sitio web. .