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Study on Ovulation Inhibition with Levonorgestrel Tablets for Contraception in Women with Intentional Intake Errors

InvestigationalNo placebo
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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 the effects of a medication called Levonorgestrel, which is used for contraception. The study aims to understand how well this medication can prevent ovulation, which is the release of an egg from the ovary, even when there are intentional delays in taking the tablet. The trial involves taking Levonorgestrel tablets continuously over three 28-day cycles.

The purpose of the study is to investigate if the prevention of ovulation is maintained despite scheduled delays in taking the medication. Participants will take the Levonorgestrel tablet daily, and the study will observe how effective the medication is in preventing ovulation during this period. The trial is designed to simulate real-life scenarios where a person might forget to take their contraceptive pill on time.

Throughout the study, participants will be monitored to see if ovulation occurs, which is determined by specific hormone levels in the body. The trial will help to provide more information on the reliability of Levonorgestrel as a contraceptive method, even when there are occasional delays in taking the pill. This research is important for understanding how to improve contraceptive options and ensure their effectiveness in everyday use.

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

    Beginning of the trial

    Upon joining the clinical trial, you will start by taking a medication called levonorgestrel. This is a tablet that you will take by mouth.

    The dosage of the tablet is 0.135 mg, and you will take it once every day.

  2. Step 2

    First cycle

    The trial consists of three cycles, each lasting 28 days. During the first cycle, you will take the levonorgestrel tablet daily without any intentional delays.

    It is important to take the tablet at the same time each day to maintain consistency.

  3. Step 3

    Second cycle

    In the second cycle, you will continue taking the levonorgestrel tablet daily. However, there will be scheduled delays in taking the tablet to test the effect on ovulation inhibition.

    These delays are intentional and part of the study design to understand how timing affects the medication's effectiveness.

  4. Step 4

    Third cycle

    During the third cycle, you will again take the levonorgestrel tablet daily with intentional intake errors as instructed by the study team.

    The purpose is to further investigate the impact of these errors on the prevention of ovulation.

  5. Step 5

    End of the trial

    At the end of the three cycles, your participation in the trial will conclude.

    You may be asked to attend a final visit to discuss your experience and any observations you may have had during the trial.

Who can join the trial?

8 criteria

  • Provide written informed consent after being informed about the benefits and potential risks of the clinical trial, as well as details of the insurance covering participants.
  • Must be female and premenopausal (before menopause).
  • Age must be between 18 years to 35 years inclusive at the time of screening.
  • Have a Body Mass Index (BMI) of at least 18.0 kg/m² at screening. BMI is a measure of body fat based on height and weight.
  • Be in a good state of physical and mental health based on medical, surgical, and gynecological history, as well as physical and gynecological examination at screening.
  • Must be a non-smoker or an ex-smoker for at least 3 months if over 30 years old, or a moderate smoker (10 cigarettes or 2 cigars or 2 pipes per day) if 30 years old or younger; this will be checked at the screening examination.
  • Both ovaries must be visible upon transvaginal ultrasonography (TVUS), which is an ultrasound test done through the vagina, observed at the screening examination.
  • Must have ovulation in the pre-treatment cycle, defined as a serum progesterone concentration greater than 10.0 nmol/l on cycle day 20 (±4) or 25 (±4). Progesterone is a hormone that indicates ovulation has occurred.

Who cannot join the trial?

10 criteria

  • Participants must not be pregnant or planning to become pregnant during the study.
  • Participants should not have any known allergies to the study medication.
  • Participants must not have any serious health conditions that could interfere with the study.
  • Participants should not be using any other form of hormonal contraception.
  • Participants must not have a history of blood clots or any condition that increases the risk of blood clots.
  • Participants should not have any liver disease or liver problems.
  • Participants must not be breastfeeding during the study.
  • Participants should not have any history of breast cancer or any other hormone-sensitive cancer.
  • Participants must not be taking any medications that could interfere with the study medication.
  • Participants should not have any mental health conditions that could affect their ability to participate in the study.
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Investigated drugs

Levonorgestrel is a type of medication used in this clinical trial to prevent ovulation, which means it helps stop the release of an egg from the ovary. This medication is taken in the form of a tablet every day. The trial is designed to see if this medication can still prevent ovulation even if there are planned delays in taking the tablets. This means that the study is checking if the medication is effective even when the schedule for taking it is not followed exactly. Levonorgestrel is often used in birth control pills and works by changing the way hormones in the body function to prevent pregnancy. In this trial, the focus is on understanding how well it works when the intake schedule is not perfect.

What is already known about the treatment

Levonorgestrel tablet, 0.135 mg – This medication is taken orally in the form of a tablet and is used as a contraceptive to prevent ovulation. It is currently being studied in clinical trials to see if it can still effectively prevent ovulation even when there are intentional delays in taking the tablets. The main use of this medication is for contraception, helping to prevent pregnancy. It works by altering hormone levels in the body to stop the release of an egg from the ovary. Levonorgestrel is classified as a progestin, which is a type of hormone used in birth control.

Investigated diseases

Ovulation Inhibition – Ovulation inhibition refers to the prevention of the release of an egg from the ovary. This process is a key mechanism in hormonal contraception, where specific hormones are used to suppress the natural menstrual cycle. The inhibition is achieved by altering the hormonal signals that trigger ovulation, primarily through the use of progestins. When ovulation is inhibited, the likelihood of fertilization and pregnancy is significantly reduced. The process involves maintaining hormone levels that prevent the maturation and release of eggs. This method is effective as long as the hormonal levels are consistently maintained.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-521236-12-00Protocol code1460lng24ctEstimated enrolment34 patientsSponsorSocraTec R&D Concepts in Drug Research and Development GmbH

sourced from the EU Clinical Trials Register and site verification

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