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Study Comparing Progesterone and Ganirelix for Preventing LH Surge in Women Undergoing Ovarian Stimulation for Egg Donation

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on women who are undergoing ovarian stimulation as part of an oocyte donation process. The study is investigating the effectiveness of two different treatments in preventing a surge in a hormone called luteinizing hormone (LH) during this process. The treatments being compared are micronized natural progesterone (known as Seidigestan) and a type of medication called gonadotropin-releasing hormone (GnRH) antagonists, specifically Astarté. The main goal is to see if the progesterone treatment is not less effective than the GnRH antagonist treatment.

Participants in the study will receive one of the two treatments. Seidigestan is taken orally in the form of soft capsules, while Astarté is administered as a solution for injection. The study will monitor the number of mature eggs, known as oocytes, that are obtained during the ovarian stimulation process. This will help determine which treatment is more effective in managing the hormone levels during the procedure.

The study will take place over a period of time, with participants receiving their assigned treatment and undergoing regular monitoring to assess the outcomes. The results will provide valuable information on the best approach to prevent LH surges during controlled ovarian stimulation, which is an important aspect of successful oocyte donation. The findings could potentially improve the protocols used in fertility treatments and oocyte donation programs.

The research process

The trial runs in 7 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial visit and screening

    Upon joining the study, eligibility is confirmed based on criteria such as age, body mass index (BMI), and antral follicle count. Understanding of Spanish and written consent are required.

    A detailed explanation of the study protocol is provided, ensuring comprehension and ability to comply with the study requirements.

  2. Step 2

    Start of medication

    The first medication, follitropin alfa, is administered as a subcutaneous injection. The dosage is either 150 IU/0.25 mL or 225 IU/0.375 mL, depending on individual needs.

    This medication is used to stimulate the ovaries and is administered daily.

  3. Step 3

    Prevention of premature ovulation

    To prevent premature ovulation, triptorelin or ganirelix is administered as a subcutaneous injection. The dosage for triptorelin is 0.1 mg, and for ganirelix, it is 0.25 mg/0.5 mL.

    These medications are administered daily during the stimulation phase.

  4. Step 4

    Ovarian stimulation monitoring

    Regular monitoring through ultrasound and blood tests is conducted to assess the response to the medication and adjust dosages if necessary.

    The goal is to ensure optimal stimulation of the ovaries while preventing complications.

  5. Step 5

    Final maturation of oocytes

    Once the follicles reach the desired size, a final injection is given to mature the oocytes. This is typically done with a different medication, not specified in the trial data.

    Timing is crucial for this step to ensure the oocytes are ready for retrieval.

  6. Step 6

    Oocyte retrieval

    The oocytes are retrieved in a minor surgical procedure, usually performed under sedation.

    The number of oocytes retrieved is a primary endpoint of the study.

  7. Step 7

    Post-retrieval follow-up

    After the retrieval, follow-up visits are scheduled to monitor recovery and any potential side effects.

    Additional assessments may be conducted to evaluate the number of oocytes suitable for further procedures.

Who can join the trial?

8 criteria

  • Be eligible to enter the Instituto Bernabeu's oocyte donation program.
  • Age between 18 and 33 years.
  • BMI (Body Mass Index) greater than 18 and less than 30.
  • Antral follicle count greater than 8, adding both ovaries. This means having a certain number of small follicles in the ovaries.
  • Presence of both ovaries.
  • Ability to participate and comply with the study protocol, meaning you can follow the study's rules and procedures.
  • Understand Spanish orally and in writing.
  • Have given written consent, which means you agree to participate in the study by signing a form.

Who cannot join the trial?

3 criteria

  • Women who are not undergoing ovarian stimulation for oocyte donation cannot participate. Ovarian stimulation is a process where medications are used to encourage the ovaries to produce multiple eggs.
  • Men cannot participate in this study.
  • Individuals who are considered part of a vulnerable population cannot participate. A vulnerable population includes groups who may have limited ability to give informed consent or are at higher risk of being exploited.
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Investigated drugs

  • Micronized Natural Progesterone (Seidigestan®)

    is a form of the hormone progesterone that has been processed into tiny particles to help the body absorb it more easily. In this trial, it is used to help control the timing of ovulation by preventing a hormone surge that can cause the ovaries to release eggs too early. This helps doctors better manage the process of stimulating the ovaries to produce eggs for fertility treatments.

  • GnRH Antagonists (Astarté®)

    are medications that block the action of a natural hormone in the body called GnRH. By doing this, they help prevent the release of another hormone called LH, which can trigger ovulation. In this trial, the GnRH antagonist is used to help control when ovulation happens, allowing for better timing in fertility treatments.

What is already known about the treatment

  • Seidigestan

    Seidigestan is administered orally in the form of micronized natural progesterone capsules. It is currently being studied in clinical trials to assess its effectiveness in preventing premature LH surges during controlled ovarian stimulation, particularly for women donating eggs. The medication works by supplementing the body's natural progesterone levels, which helps regulate the hormonal balance necessary for successful ovarian stimulation. Seidigestan is classified as a progestogen, a type of hormone therapy used in reproductive medicine.

  • Astarté

    Astarté is administered via injection and is used in the context of controlled ovarian stimulation to prevent premature LH surges. It is currently being evaluated in clinical trials for its effectiveness compared to other protocols in women undergoing ovarian stimulation for egg donation. Astarté functions by blocking the action of GnRH (gonadotropin-releasing hormone), which in turn prevents the release of LH (luteinizing hormone) and FSH (follicle-stimulating hormone), helping to control the timing of ovulation. It is classified as a GnRH antagonist, a type of medication used to manage reproductive hormone levels.

Investigated diseases

Ovarian Hyperstimulation Syndrome – Ovarian Hyperstimulation Syndrome (OHSS) is a condition that can occur in women who are undergoing fertility treatments, particularly those involving hormone injections to stimulate the ovaries. The condition is characterized by swollen and painful ovaries. As the syndrome progresses, fluid may leak into the abdomen and chest, causing bloating, nausea, and discomfort. In more severe cases, it can lead to rapid weight gain, severe abdominal pain, and shortness of breath. The symptoms typically develop within a week after the use of injectable hormone medications. The severity of the condition can vary, with some women experiencing mild symptoms and others experiencing more significant discomfort.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-504188-18-00Protocol codeIBMR43Estimated enrolment150 patientsSponsorInstituto Bernabeu S.L.

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