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Completed

NCT Number: NCT04002141

Assessment and Prevention of Pain During Ovarian Stimulation in Patients With Endometriosis

Randomized double blinded placebo-controlled trial to evaluate the impact of ovarian hyperstimulation on endometriosis-related symptoms and to evaluate the impact of letrozole use during ovarian hyperstimulation with respect to endometriosis-related symptoms, embryo/egg quality and quantity, and pregnancy rates.

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Key information

Conditions

Endometriosis Female Urogenital Diseases Female Urogenital Diseases and Pregnancy Complications Genital Diseases Genital Diseases, Female Ovarian Hyperstimulation Urogenital Diseases

Age range

18 year–42 year

Sex eligibility

Female

Study type

Interventional

Phase

Phase 2

Primary location

UCSF Center for Reproductive Health

San Francisco, California, 94158, United States

About this study

Randomized double blinded placebo-controlled trial to evaluate: (1) the impact of letrozole use during ovarian hyperstimulation with respect to endometriosis-related symptoms, embryo/egg quality and quantity, and pregnancy rates, (2) the impact of ovarian hyperstimulation on endometriosis-related symptoms.

There will be a total of 60 participants, 20 participants with endometriosis randomized to the placebo group, 20 participants with endometriosis randomized to the letrozole group and 20 control patients with no history of endometriosis. Letrozole and placebo medication will be started on the first day of gonadotropin injections and continued until the day of trigger shot. Medication will be restarted the night of egg retrieval and continued for 2 weeks post retrieval. Endometriosis associated symptoms will be evaluated using a survey modeled after the clinical survey developed by the World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonisation Project. Surveys will be administered at baseline ultrasound appointment for controlled ovarian hyperstimulation cycle, the day of trigger shot, 3 weeks following egg retrieval, 6 weeks following egg retrieval and 12 weeks following egg retrieval.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Age 18-42 years
  • Planning to undergo controlled ovarian hyperstimulation
  • Prior diagnosis of endometriosis by one of the following: (1) surgical diagnosis (2) endometrioma on pelvic ultrasound
  • Planning to freeze all retrieved oocytes/embryos prior to transfer

Exclusion criteria

  • Hypersensitivity to letrozole
  • Any significant concurrent disease, illness, or psychiatric disorder that would compromise patient safety or compliance, interfere with consent, study participation, follow-up, or interpretation of study results

Treatment and study plan

Placebo oral tablet

Drug

1 tablet oral daily

letrozole

Drug

5mg oral daily

Primary outcomes

  1. Average Delta in Endometriosis Pain Score Pre and Post Stimulation With and Without Use Of Letrozole

    Time frame: Baseline ultrasound (day 2 of menstrual cycle) and day 12 (average day of trigger shot).

    To evaluate how letrozole impacts pain scores throughout controlled ovarian hyperstimulation in patients with endometriosis. Pain scores will be evaluated using a 0-10 visual acuity scale, where 0 is no pain and 10 is the worst imaginable pain. The average delta between pre-stimulation pain score and day of trigger shot pain score will be compared between patients with endometriosis receiving placebo and with endometriosis receiving letrozole.

Secondary outcomes

  1. Average Delta in Endometriosis Pain Score Pre and Post Stimulation of Patients Receiving Placebo Compared to No Endometriosis

    Time frame: Baseline ultrasound (day 2 of menstrual cycle) and day 12 (average day of trigger shot).

    To evaluate the impact of endometriosis on pain scores throughout controlled ovarian hyperstimulation. Pain scores will be evaluated using a 0-10 visual acuity scale, where 0 is no pain and 10 is the worst imaginable pain. The average delta between pre-stimulation pain score and day of trigger shot will be compared between patients with endometriosis receiving placebo and patients without endometriosis.

  2. Comparative Trends in Endometriosis Pain Score Pre and Post Stimulation of Patients With Endometriosis Receiving Either Placebo or Letrozole and Patients Without Endometriosis

    Time frame: Pre-stimulation through 12 weeks post retrieval. This time span varies per each patient's course of treatment but is typically 14 weeks in tota

    To evaluate the impact of letrozole on endometriosis pain scores throughout controlled ovarian hyperstimulation. Pain scores will be evaluated using a 0-10 visual acuity scale, where 0 is no pain and 10 is the worst imaginable pain. The calculated change in pain scores from pre-stimulation through 12 weeks post retrieval will be compared between patients with endometriosis receiving placebo, patients with endometriosis receiving letrozole and patients without endometriosis.

  3. Does Letrozole Impact Egg Quantity in Endometriosis Patients

    Time frame: Baseline ultrasound (day 2 of menstrual cycle) and day 14 (average day of egg retrieval).

    To describe the impact of letrozole on egg quantity in patients with endometriosis receiving letrozole and those with endometriosis not receiving letrozole and those without endometriosis during controlled ovarian stimulation. The total arm aggregate number of MII eggs retrieved per baseline arm aggregate Antral Follicle Count will be compared between the three groups.

  4. Follicular Fluid

    Time frame: Baseline ultrasound (day 2 of menstrual cycle) and day 14 (average day of egg retrieval).

    To compare follicular fluid average estradiol levels between placebo, letrozole and control groups.

  5. Pregnancy Outcomes

    Time frame: Up to 2 years.

    To compare pregnancy rates in the placebo, letrozole and control groups. Pregnancy will be defined as positive serum hCG after transfer of embryo. The rate will determined by positive hCG per transfer.

  6. Egg Maturity

    Time frame: Baseline ultrasound to time of cryopreservation of eggs/embryos, which occurs within 7 days of retrieval..

    To describe the impact of letrozole on egg maturity. Measured by number of MII eggs per total number eggs retrieved in patients with endometriosis receiving letrozole and those with endometriosis not receiving letrozole during controlled ovarian stimulation.

  7. Embryo Grade

    Time frame: 2 weeks

    To describe the impact of letrozole on embryo quality. Measured by the average total number of freezable quality embryos (6c or greater, grades 1-2 for symmetry and fragmentation) in patients with endometriosis receiving letrozole and those with endometriosis not receiving letrozole and those without endometriosis during controlled ovarian stimulation.

Sponsors and collaborators

Lead sponsor

University of California, San Francisco

Other

Registry information

Acronym: APPOSE

Important dates

Study start
2019
Primary completion
2023
Study completion
2025
First posted
Jun 28, 2019
Registry last updated
Jan 28, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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