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Study Comparing Intranasal Nafarelin and Subcutaneous Triptorelin for Final Egg Maturation in Women with Infertility

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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 studying infertility, a condition where individuals have difficulty getting pregnant. The study is comparing two treatments used to help mature eggs in the ovaries during a process called ovarian stimulation. The first treatment is an intranasal spray called nafarelin, and the second is a subcutaneous injection called triptorelin. Both treatments are used to trigger the final maturation of eggs, which is an important step in fertility treatments.

The purpose of the study is to compare the effectiveness of these two treatments in helping retrieve mature eggs, known as metaphase II oocytes, during a specific type of fertility treatment cycle called progesterone-primed ovarian stimulation. Participants in the study will receive either the nafarelin nasal spray or the triptorelin injection. The study will monitor the number of mature eggs retrieved, as well as other factors like the total number of eggs collected, any side effects, and the participants' experiences with the treatments.

The study will take place over a period of time, with participants undergoing the treatment and then having their eggs collected. The researchers will gather data on the outcomes to determine which treatment is more effective or if they are equally effective. This information could help improve fertility treatments for individuals experiencing infertility.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the trial

    Upon joining the study, you will be informed about the trial's purpose, procedures, and your role as a participant. You will be asked to provide consent to participate in the trial.

  2. Step 2

    Initial assessment

    You will undergo an initial assessment to confirm eligibility. This includes checking your age, body mass index (BMI), and the number of follicles in your ovaries. You must be between 18 and 35 years old, have a BMI between 18 and 30 kg/m2, and have at least 10 follicles of 14mm average diameter.

  3. Step 3

    Medication administration

    You will be randomly assigned to receive either intranasal nafarelin or subcutaneous triptorelin to trigger final oocyte maturation. Nafarelin is administered as a nasal spray, while triptorelin is given as an injection under the skin.

    The dosage and frequency of administration will be explained to you by the medical team. The duration of this stage will depend on your specific treatment plan.

  4. Step 4

    Monitoring and follow-up

    After medication administration, you will be monitored for the number of mature eggs (oocytes) retrieved. Blood tests will be conducted to measure hormone levels, including LH, FSH, and progesterone.

    You will be asked to report any side effects, pain, or preferences regarding the medication used.

  5. Step 5

    Completion of trial

    Once the trial is completed, you will receive a summary of your participation and any relevant findings. Your feedback on the ease of use and preference for the medication will be collected.

Who can join the trial?

5 criteria

  • Age between 18 and 35 years old.
  • Must be an oocyte donor (a person who donates eggs for fertility treatments).
  • Undergoing a progesterone-primed ovarian stimulation cycle (PPOS), which is a specific type of fertility treatment using any available hormone medications to stimulate the ovaries.
  • Body Mass Index (BMI) between 18 and 30 kg/m2. BMI is a measure of body fat based on height and weight.
  • At least 10 follicles (small sacs in the ovaries that contain eggs) with an average diameter of 14mm or more on the last ultrasound before the trigger medication is given.

Who cannot join the trial?

9 criteria

  • Participants must not have any medical conditions that could interfere with the study.
  • Participants must not be using any medications that could affect the study results.
  • Participants must not have a history of allergic reactions to any of the study medications.
  • Participants must not be pregnant or breastfeeding.
  • Participants must not have any significant health issues that could pose a risk during the study.
  • Participants must not have participated in another clinical trial recently.
  • Participants must not have any mental health conditions that could affect their ability to participate in the study.
  • Participants must not have any substance abuse issues.
  • Participants must not have any other conditions that the study doctors think would make it unsafe for them to participate.
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Investigated drugs

  • Nafarelin

    is a medication used in this clinical trial to help mature eggs in the ovaries. It is administered through the nose, which means you spray it into your nostrils. This medication helps trigger the final stage of egg development, making the eggs ready for retrieval in fertility treatments.

  • Triptorelin

    is another medication used in the trial for the same purpose as nafarelin. However, it is given as an injection under the skin. Like nafarelin, triptorelin helps the eggs in the ovaries reach their final stage of maturity, so they can be collected for fertility procedures.

What is already known about the treatment

  • Nafarelin

    Nafarelin is administered as a nasal spray, making it easy to use. It is currently being studied in clinical trials for its effectiveness in helping with infertility, specifically in the process of maturing eggs in the ovaries. Nafarelin works by influencing hormone levels in the body to help mature eggs, which is crucial for successful fertilization. It belongs to a group of medications known as gonadotropin-releasing hormone (GnRH) agonists, which are used to manage hormone-related conditions.

  • Triptorelin

    Triptorelin is given as an injection under the skin, which is a common method for delivering medications directly into the bloodstream. It is being evaluated in clinical trials for its role in treating infertility by aiding in the final maturation of eggs in the ovaries. Triptorelin functions by adjusting hormone levels to support the development of mature eggs, essential for conception. It is classified as a GnRH agonist, a type of medication used to regulate hormone activity in various medical conditions.

Investigated diseases

Infertility – Infertility is a condition where an individual is unable to conceive after a year of regular, unprotected sexual intercourse. It can affect both men and women and may result from various factors, including hormonal imbalances, structural problems, or issues with sperm or egg production. In women, infertility may be linked to ovulation disorders, blocked fallopian tubes, or uterine abnormalities. In men, it often involves low sperm count, poor sperm motility, or blockages that prevent sperm delivery. The progression of infertility depends on the underlying cause, which may remain stable or worsen over time. Environmental factors, lifestyle choices, and age can also influence the progression of infertility.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-516621-31-00Protocol codeFSD-NAF-2024-11Estimated enrolment154 patientsSponsorSantiago Dexeus Font Fundacio Privada

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).