Efficacy of Micronized Natural Progesterone vs GnRH Antagonist in the Prevention of LH Peak During Ovarian Stimulation. (PRO_NAT)

March 23, 2026 updated by: Maria Martinez Moya, Instituto Bernabeu

Evaluation of the Efficacy of Micronized Natural Progesterone (Seidigestan®) vs GnRH Antagonist (Astarté®) in the Prevention of LH Peak During Controlled Ovarian Stimulation: a Randomized Clinical Trial.

This study aims to investigate if the use of oral micronized natural progesterone is not inferior to the use of subcutaneous antagonist in preventing LH peak in controlled ovarian stimulation.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

The study will aim to include 150 women (egg donors): 75 per group and the principal variable will be the number of retrieved mature (MII) oocytes. Randomized, prospective, controlled, single center, phase IV study.

Study Type

Interventional

Enrollment (Actual)

150

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Spain
    • Alicante
      • Elche, Alicante, Spain, 03206
        • Instituto Bernabeu

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Eligibility for the oocyte donation program at Instituto Bernabeu.
  • Age between 18 and 33 years
  • BMI >18 and <30
  • Overall antral follicle count >8
  • Presence of both ovaries
  • Ability to participate and comply with the study protocol
  • Oral and written comprehension of Spanish
  • Having given written consent

Exclusion Criteria:

  • Endometriosis at any stage
  • Any ovarian tumor whether benign or malignant
  • Concurrent participation in another study
  • Malabsorptive syndromes that may alter the efficacy of Seidigestan ® such as bariatric surgery, ulcerative colitis or Crohn's disease
  • Irregular periods
  • Hypogonadotropic hypogonadism
  • Having received in the previous two months treatment with ovulation stimulators
  • Having previously participated in the present study

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: CONTROL GROUP
The patient will start to administer: (1) daily subcutaneous injections of gonadotropins on day 1 of ovarian stimulation (2) daily subcutenous injections of ganirelix ("antagonist") on day 5 or 6 of ovarian stimulation. Both medication will be stopped 1-2 days before egg retrieval.
Drug: Ganirelix Acetate
The patients in the control group will administer subcutaneaous injections of ganirelix from day 5-6 of stimulation as per currently used protocol.
Experimental: STUDY GROUP
The patient will start to administer: (1) daily subcutaneous injections of gonadotropins on day 1 of ovarian stimulation (2) daily oral capsules of natural micronized progesterone on day 1 of ovarian stimulation. Both medication will be stopped 1-2 days before egg retrieval.
Drug: Progesterone 200 MG
The patients in the study group will administer oral natural micronized progesterone capsules from day 1 of ovarian stimulation instead of "antagonist" (ganirelix) subcutaneaous injections from day 5-6 of stimulation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
MII oocytes
Time Frame: Egg collection day (between 8 and 14 days after starting of ovarian stimulation)
number of mature (MII) oocytes in both stimulations.
Egg collection day (between 8 and 14 days after starting of ovarian stimulation)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Duration
Time Frame: Egg collection day (between 8 and 14 days after starting of ovarian stimulation)
duration of ovarian stimulation under both protocols.
Egg collection day (between 8 and 14 days after starting of ovarian stimulation)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Instituto Bernabeu

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 23, 2023

Primary Completion (Actual)

April 3, 2025

Study Completion (Actual)

August 30, 2025

Study Registration Dates

First Submitted

July 12, 2023

First Submitted That Met QC Criteria

July 12, 2023

First Posted (Actual)

July 20, 2023

Study Record Updates

Last Update Posted (Actual)

March 27, 2026

Last Update Submitted That Met QC Criteria

March 23, 2026

Last Verified

November 1, 2024

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • IBMR43

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

The information collected in the study will always be treated as grouped data and never as individual or personal data, thus maintaining anonymity and confidentiality.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on IVF

Clinical Trials on Ganirelix Acetate

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Mexico

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe