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A study comparing the effects of estetrol and drospirenone, ethinylestradiol and drospirenone, and drospirenone in women with polycystic ovary syndrome (PCOS)

Verified siteRegistered drugNo placebo
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What is this trial about?

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

This study focuses on women with Polycystic Ovary Syndrome, a condition that affects hormone levels. The purpose of the study is to investigate how different types of contraception, which are methods used to prevent pregnancy, affect blood clotting. Participants will be assigned to use different medications taken by mouth, including estetrol and drospirenone, ethinylestradiol and drospirenone, or only drospirenone.

During the trial, individuals will take one of the three different medication combinations for a period of six months. The study will look at how these treatments impact coagulation, which is the process the body uses to form clots in the blood. By comparing these options, researchers aim to see if certain hormone combinations have a smaller effect on the blood's ability to clot compared to others.

The research process

The trial runs in 2 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Medication administration

    You will be assigned to take one of three different types of oral medication (pills taken by mouth) for a period of 6 months.

    The first option is a combination of estetrol and drospirenone (drovelis 3 mg/14.2 mg film-coated tablets).

    The second option is a combination of ethinylestradiol and drospirenone (daylette 0,02 mg / 3 mg film-coated tablets).

    The third option is drospirenone only (slinda 4 mg film-coated tablets).

  2. Step 2

    Study conclusion

    After the 6-month period of using the assigned medication, an endpoint visit will occur to complete the study process.

Who can join the trial?

8 criteria

  • You must be a female between the ages of 18 and 40 when you start the study.
  • You must be willing to take the study medication and sign a written informed consent, which is a formal document where you agree to participate after being told about the study details.
  • Your BMI (Body Mass Index, a measure of body fat based on your height and weight) must be between 18 and 29.9 kg/m2.
  • You must have been diagnosed with PCOS (Polycystic Ovary Syndrome, a condition that affects hormone levels in women) based on specific medical rules called the Rotterdam criteria. This means you must show signs of hyperandrogenism (excess male-type hormones), PCOM (the presence of small cysts on the ovaries seen on an ultrasound), or menstrual irregularities (unpredictable or irregular periods).
  • Aside from PCOS, you must be healthy with no other significant illnesses or ongoing medical treatments.
  • You must have stopped using hormonal contraceptive medication (birth control) at least two months before the study begins.
  • It must have been at least three months since your last pregnancy or since you finished breastfeeding.
  • You must have enough knowledge of Finnish to read the study documents and talk to the research team.

Who cannot join the trial?

5 criteria

  • You have a medical reason why you cannot use combined contraceptives, which are birth control methods that use more than one type of hormone.
  • You have any clinically significant abnormalities, which means important or concerning health issues, found during your medical tests or ultrasound (a way to see inside the body using sound waves).
  • You are a regular smoker, use nicotine products (such as patches or gum), use illegal drugs, or have a problem with alcohol abuse.
  • You are planning to become pregnant while participating in this study.
  • You have any disease or condition that could make it difficult to complete the study or could make the results of the study difficult to understand.
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Investigated drugs

  • Drovelis

    is a combined hormonal contraceptive pill that contains two types of hormones, estetrol and drospirenone, taken orally to prevent pregnancy.

  • Slinda

    is a hormonal contraceptive pill containing only drospirenone, taken orally to prevent pregnancy.

  • Daylette

    is a combined hormonal contraceptive pill that contains two types of hormones, ethinylestradiol and drospirenone, taken orally to prevent pregnancy.

What is already known about the treatment

  • Drovelis

    This medication is taken orally in the form of a film-coated tablet and is used as a combined hormonal contraceptive. It contains two active substances, drospirenone and estetrol, which work together to prevent pregnancy by stopping the ovaries from releasing eggs and thickening cervical mucus. Drospirenone is a progestogen that mimics natural hormones to regulate the cycle, while estetrol is a newer type of estrogen designed to provide reproductive control with specific metabolic effects.

  • Slinda

    This is a progestogen-only contraceptive pill taken orally as a film-coated tablet. It contains drospirenone, a medication that prevents pregnancy primarily by suppressing ovulation and thickening the mucus on the cervix to block sperm. It is used as a single-hormone contraceptive option for women who may not require estrogen.

  • Daylette

    Taken orally as a film-coated tablet, this medication is a combined hormonal contraceptive used to prevent pregnancy. It contains both drospirenone and ethinylestradiol, which work by preventing the body from releasing eggs and altering the uterine lining. The combination of these two hormones provides highly effective birth control by mimicking and regulating the natural hormonal cycle.

Investigated diseases

Contraception - This refers to the use of various methods or substances to prevent pregnancy. It involves processes that stop the release of eggs from the ovaries or prevent a fertilized egg from attaching to the uterus. These methods can be used temporarily or long-term to manage reproductive functions. The effectiveness depends on how the substances interact with the body's natural hormonal cycles.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2025-523358-15-00Protocol codeCoCo3-PCOSEstimated enrolment156 patientsSponsorPohjois-Pohjanmaan hyvinvointialue

sourced from the EU Clinical Trials Register and site verification

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