Efficacy of Oral Contraceptive, Progesterone, and Inositol on Menstrual Regulation in PCOS

Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting women of reproductive age and is characterized by chronic anovulation, hyperandrogenism, and polycystic ovarian morphology. It is one of the most prevalent causes of infertility and is frequently associated with metabolic abnormalities such as insulin resistance, obesity, and dyslipidemia.

The primary treatment goal in PCOS is to restore regular ovulatory cycles, improve ovarian morphology, and reduce hyperandrogenic symptoms such as hirsutism and acne.

Combined oral contraceptives (COCs) are the first-line pharmacological option for cycle regulation in PCOS; however, their use is contraindicated in women with risk factors such as smoking, thromboembolic disorders, severe hepatic dysfunction, uncontrolled hypertension, or a history of breast cancer. Additionally, COCs are not suitable for women who desire pregnancy in the near future.

Therefore, alternative treatments that can effectively regulate menstrual cycles without suppressing fertility or inducing metabolic risks are clinically relevant.

This study aims to compare the effects of oral contraceptives, oral progesterone, and myo-inositol on menstrual regulation and ovarian morphology in women diagnosed with PCOS.

A total of 150 women aged 15-40 years who meet the ESHRE/ASRM (Rotterdam) diagnostic criteria for PCOS will be enrolled at the Department of Obstetrics and Gynecology, İzmir Bakırçay University Çiğli Training and Research Hospital. Participants will be randomly assigned to one of three groups (n=50 per group):

Group 1: Oral contraceptive users

Group 2: Oral progesterone users (didrogesterone 10 mg, twice daily, cyclic regimen)

Group 3: Inositol users (2 g/day)

Clinical parameters including menstrual regularity, body mass index, hirsutism score, acne grade, and ovarian morphology (assessed via transvaginal or transabdominal ultrasonography) will be recorded at baseline and follow-up visits.

The primary outcome will be restoration of regular menstrual cycles. Secondary outcomes will include changes in ovarian morphology, reduction of hyperandrogenic symptoms, and treatment tolerability.

Data will be analyzed using appropriate parametric or non-parametric statistical tests, with significance set at p<0.05.

All patient data will be anonymized, and participation will be voluntary following written informed consent. The study has been approved by the İzmir Bakırçay University Non-Interventional Clinical Research Ethics Committee.

Inclusion criteria

• Female participants aged 18 to 40 years.
• Diagnosed with polycystic ovary syndrome (PCOS) according to the ESHRE/ASRM (Rotterdam) criteria (presence of at least two of the following: oligo/anovulation, clinical or biochemical hyperandrogenism, polycystic ovarian morphology).
• No significant comorbid systemic disease.
• Willingness to participate and ability to provide written informed consent.
• Regular follow-up availability for at least 6 months.

Exclusion criteria

• Known hepatic, renal, cardiovascular, or endocrine disorders other than PCOS.
• Pregnancy or current use of hormonal therapy within the past 3 months.
• History of thromboembolic disease, breast cancer, or other contraindications to hormonal treatment.
• Inability to adhere to follow-up visits or treatment regimen.
• Severe cognitive or communication impairment that prevents proper consent or data collection.
• Known allergy or hypersensitivity to any component of the study drugs.
• Participation in another interventional study within the past 3 months.