Effects of Letrozole During the Luteal Phase After Controlled Ovarian Stimulation in Oocyte Donors.

Phase 3

Recruiting

• Conditions: Luteinised Follicular Cyst
• Interventions: Drug: Administration of letrozole

• Registration Number: NCT06244745
• Lead Sponsor: IVI Madrid

Brief Summary

The objective of this trial is to determine whether the use of letrozole during the luteal phase in oocyte donors diminishes the ovarian volume, as well as to evaluate its effect on the duration of the luteal phase, taking into account hormonal and biochemical markers.

Two groups will be established with random allocation of patients and 1:1 proportionality, as follows:

* Control group: No specific treatment.

* Study group: Oral administration of letrozole 5 mg (each capsule is 2.5 mg) once a day for 5 days starting on the night of the follicular puncture.

Detailed Description

Letrozole is a widely used drug in the context of hormone-dependent malignant tumors due to its antiestrogenic effect. Its mechanism of action allows its application to the field of Assisted Reproductive Medicine, mainly as an inductor of ovulation, by means of a blockage in the negative feedback signalization of the hypothalamus-pituitary-gonadal axis. In the last years, it has also been tested with the goals of preventing ovarian hyperstimulation syndrome (OHSS) or analyzing its effects on several endocrinological and biochemical markers such as LH, progesterone or VEGF. However, the results are inconsistent on every account. Data regarding the effect on ovarian size and the duration of the luteal phase following the administration of letrozole after the oocyte pick-up can be useful to evaluate the benefit of this drug in patients with a tendency towards hyperresponse, in which both the discomfort after the stimulation and the risk of ovarian torsion are increased.

The objective of this trial is to determine whether the use of letrozole during the luteal phase in oocyte donors diminishes the ovarian volume, as well as to evaluate its effect on the duration of the luteal phase, taking into account hormonal and biochemical markers

Study Timeline

• Study Start: 2023-12-15
• Study First Submitted: 2024-01-11
• Study First Submitted QC: 2024-02-05
• Study First Posted: 2024-02-06
• Status Verified: 2025-02
• Primary Completion: 2025-05-01
• Last Update Submitted: 2025-05-20
• Last Update Posted: 2025-05-21
• Study Completion: 2025-05-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 152

Inclusion Criteria

• Hyper-responsiveness to stimulation, defined as the presence of ≥18 follicles of size ≥11 mm (22-24) on the day of the last ultrasound visit prior to ovarian puncture.

Exclusion Criteria

• Participation in another clinical study, prior to inclusion in the present study, that could affect the objectives of this study.
• Known allergy to letrozole.
• Known lactose intolerance.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Study group: Oral administration of letrozole	Administration of letrozole	Oral administration of letrozole 5 mg (each capsule is 2.5 mg) once a day for 5 days starting on the night of the follicular puncture. day for 5 days starting the night of the follicular puncture.

Primary Outcome Measures

Name	Time	Method
To determine ovarian volume in millilitres in oocyte donors according to whether or not they receive the treatment during the luteal phase after ovarian stimulation.	On the day of ovarian puncture, 5 days post-puncture and 10 days post-puncture.	Difference (in millilitres) in the mean volume of the two ovaries, calculated for each ovary according to the formula for the volume of an ellipsoid

Secondary Outcome Measures

Name	Time	Method
To determine the duration of the luteal phase in oocyte donors depending on whether or not they receive the treatment under study during the luteal phase after ovarian stimulation.	On the day of ovarian puncture and 10 days post-puncture.	To determine the difference of duration of the luteal phase, inferred by the number of days from follicular puncture to the start of the next menstrual cycle. onset of the next menstrual cycle. Discrete numerical variable.
To determine the levels of VEGF, VEGF/sFlt-1 ratio, LH, FSH, oestradiol, progesterone and testosterone in the plasma of oocyte donors depending on whether or not they receive the study treatment during the luteal phase.	On the day of ovarian puncture, 5 days post-puncture and 10 days post-puncture.	To determine the difference of plasma values of VEGF, sFlt-1, oestradiol, progesterone, FSH, LH and testosterone. Ratio VEGF/sFlt-1. Continuous numerical variables.

Trial Locations

Locations (1)

IVI-Madrid; 🇪🇸 Madrid, Spain