Extended Letrozole Protocol Versus Letrozole Plus Inositol for Induction of Ovulation in Letrozole Resistant PCOS Women

June 4, 2026 updated by: Eman Basuni Ebrahim Mowad
Extended letrozole protocol versus letrozole plus Inositol for Induction of ovulation in letrozole resistant PCOS Women

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

200

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Egypt
    • Kafr el-Sheikh Governorate
      • Kafr ash Shaykh, Kafr el-Sheikh Governorate, Egypt, 33511
        • Kafrelsheikh University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Women diagnosed with polycystic ovary syndrome (PCOS) according to the Rotterdam criteria.
  • Letrozole-resistant PCOS patients who failed to ovulate after receiving letrozole 5 mg daily for 5 days for three consecutive cycles.
  • Age 18 to 35 years.
  • Body mass index (BMI) ≤ 30 kg/m².
  • Normal uterine cavity and patent fallopian tubes confirmed by hysterosalpingography (HSG) and/or laparoscopy.
  • Partner with normal semen analysis.
  • Willing and able to provide informed consent.

Exclusion Criteria:

  • Thyroid dysfunction.
  • Hyperprolactinemia.
  • Diabetes mellitus.
  • Congenital adrenal hyperplasia.
  • Adrenal causes of hyperandrogenism.
  • Use of insulin-sensitizing medications (e.g., metformin) during the study period.
  • Chronic liver disease.
  • Chronic kidney disease.
  • Contraindications to pregnancy.
  • Contraindications or hypersensitivity to inositol or letrozole.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Extended Letrozole Protocol (7 days
Drug: ELP (Extended Letrozole Protocol)

? ELP (Extended Letrozole Protocol)

Participants allocated to this arm will receive letrozole 5 mg orally once daily, starting on day 2 of the menstrual cycle and continued for 7 consecutive days.

Follicular development will be monitored using transvaginal ultrasonography every 48 hours starting after the last dose of letrozole until confirmation of ovulation.

When at least one dominant follicle reaches a mean diameter of 18-20 mm, human chorionic gonadotropin (hCG) will be administered to trigger ovulation. Timed intercourse will be advised accordingly.

Endometrial thickness will be measured on the day of ovulation trigger. This protocol may be repeated for up to 3 consecutive cycles in case ovulation is not achieved.
Experimental: Letrozole + Inositol Protocol
Drug: LIP (Letrozole + Inositol Protocol)

? LIP (Letrozole + Inositol Protocol)

Participants allocated to this arm will receive myo-inositol 2 g orally twice daily for a duration of 3 months prior to ovulation induction.

In the subsequent cycle, letrozole 5 mg orally once daily will be administered starting on day 2 of the menstrual cycle for 5 consecutive days.

Follicular monitoring will be performed using transvaginal ultrasonography every 48 hours after the last dose of letrozole until ovulation is confirmed.

Ovulation will be triggered using hCG injection when at least one follicle reaches 18-20 mm in diameter, followed by timed intercourse.

Compliance with inositol intake and any adverse effects will be documented throughout the study period.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Ovulation Rate
Time Frame: At the end of Cycle 1 (each treatment cycle is 28 days).
The proportion of participants achieving ovulation after treatment with either an extended letrozole protocol (5 mg daily for 7 days) or letrozole plus inositol protocol in letrozole-resistant PCOS women.
At the end of Cycle 1 (each treatment cycle is 28 days).

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Spontaneous Ovulation Rate
Time Frame: Up to 3 months after treatment initiation.
The proportion of participants who achieve spontaneous ovulation during the study period.
Up to 3 months after treatment initiation.
Clinical Pregnancy Rate
Time Frame: Up to 12 weeks after treatment initiation.
The proportion of participants with clinical pregnancy confirmed by transvaginal ultrasonographic visualization of a gestational sac.
Up to 12 weeks after treatment initiation.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Eman Basuni Ebrahim Mowad

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 1, 2024

Primary Completion (Actual)

June 1, 2025

Study Completion (Actual)

July 1, 2025

Study Registration Dates

First Submitted

May 18, 2026

First Submitted That Met QC Criteria

June 4, 2026

First Posted (Actual)

June 9, 2026

Study Record Updates

Last Update Posted (Actual)

June 9, 2026

Last Update Submitted That Met QC Criteria

June 4, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • Induction of ovulation

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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