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Does Letrozole Improve Pregnancy Outcome in Fresh Embryo Transfer IVF/ICSI Cycle? (IVF/ICSI)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03901170
Recruitment Status : Not yet recruiting
First Posted : April 3, 2019
Last Update Posted : April 10, 2019
Information provided by (Responsible Party):
National Taiwan University Hospital

Brief Summary:

Letrozole (Femara), is an aromatase inhibitor which is used in the treatment of hormonally-responsive breast cancer after surgery. It is a good target for selective inhibition because estrogen production is a terminal step in the biosynthetic sequence.

Aromatase inhibitors are widely used as adjuvant endocrine therapy for postmenopausal women with breast cancer. They have been used off-label in the treatment of patients for increasing the number of ovarian follicles recruited in ovulatory women undergoing controlled ovarian hyperstimulation (COH). A shorter half-life (48 hours) which would predict a lower risk of teratogenicity. No direct antiestrogenic adverse effects on the endometrium, due to an absence of peripheral estrogen receptor blockade and the shorter half-life.

For ovarian normal responders, instead of hCG (human chorionic gonadotropin), luteal support with exogenous progesterone supplementation is the standard protocol for patients who received fresh embryo transfer for avoiding the risk of OHSS. In other normal responders who have increasing risk of OHSS, the strategy of freezing all embryos are more favored.

In previous studies, high estrogen-induced endometrial gland cells apoptosis might account for the defective endometrial receptivity in women with excessively high estrogen concentrations after ovarian hyperstimulation in IVF cycles. Since letrozole can reduce the serum level of estrogen due to its pharmacological properties, which in turn reduces the adverse effects of high estrogen on the endometrium and improve the endometrial receptivity for embryo implantation.

The investigators anticipate that infertility patients will receive short-term oral administration of letrozole (2.5 mg/tab) once a day when estrogen is elevated in the late stage of ovulation stimulation when receiving ovulation stimulation for two to three days. And transvaginal ultrasound was performed every two to three days for growth of ovarian follicles until two days before oocyte retrieval. Observing whether taking the drug can improve the maturity of the oocyte, pregnancy rate, implantation rate, miscarriage rate, ongoing pregnancy rate and live birth rate of the fresh embryo transfer cycle.

Condition or disease Intervention/treatment Phase
Investigative Techniques Reproductive Techniques Reproductive Techniques, Assisted Drug: Letrozole 2.5mg Phase 4

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 300 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Compare with others who did not usage of letrozole
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Does Use of Letrozole in Controlled Ovarian Stimulation in Normal Ovarian Responder in Fresh Embryo Transfer IVF/ICSI Cycle Improve the Pregnancy Rate?
Estimated Study Start Date : April 9, 2019
Estimated Primary Completion Date : April 8, 2020
Estimated Study Completion Date : April 8, 2021

Resource links provided by the National Library of Medicine

Drug Information available for: Letrozole

Arm Intervention/treatment
Experimental: letrozole
patients with letrozole
Drug: Letrozole 2.5mg
oral administration of letrozole 2.5mg/tab, 1tab once per day from stimulation Day 7 to hCG Day.

No Intervention: control
patients without letrozole

Primary Outcome Measures :
  1. pregnancy rate [ Time Frame: 16 days after oocyte retrieval ]
  2. implantation rate [ Time Frame: 23 days after oocyte retrieval ]
    intra-uterine gestational sac/total transfer embryo number

  3. miscarriage rate [ Time Frame: gestational weeks 12 ]
    pregnancy loss before gestational weeks 12

Secondary Outcome Measures :
  1. live birth rate [ Time Frame: from gestational weeks 24 to 42 ]
    live birth with newborn

Other Outcome Measures:
  1. cumulative pregnancy rate [ Time Frame: within three months after failure to achieve pregnancy in fresh embryo transfer cycle ]
    The sequential frozen-thaw embryo transfer cycle if the patient fail at fresh embryo transfer cycle

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   20 Years to 45 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Women aged from 20 to 45 years old
  • Receive IVF treatment due to infertility
  • Plan to have fresh embryo transfer
  • Total ovarian follicle number from 8 to 15 before oocyte retrieval
  • Plan to have letrozole in IVF treatment routine

Exclusion Criteria:

  • Systemic disease, such as diabetes mellitus, hypertension, heart disease, hypothyroidism, liver or renal disease, cancer, autoimmune disease, etc.
  • Treatment cycle with pre-implantation genetic screening (PGS)/ pre-implantation genetic diagnosis(PGD)
  • Oocyte recipient
  • Poor ovarian responders according to Bologna criteria
  • Patients who have risk of Ovarian Hyperstimulation Syndrome (OHSS)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03901170

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Contact: Song-Po Pan, MD 886-2312-3456 ext 70955
Contact: Shee-Uan Chen, Professor 886-2312-3456 ext 70950

Sponsors and Collaborators
National Taiwan University Hospital

Publications of Results:
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Responsible Party: National Taiwan University Hospital Identifier: NCT03901170    
Other Study ID Numbers: 201810102MINC
First Posted: April 3, 2019    Key Record Dates
Last Update Posted: April 10, 2019
Last Verified: March 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: Study Protocol

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No
Keywords provided by National Taiwan University Hospital:
In Vitro Fertilization
endometrial receptivity
Additional relevant MeSH terms:
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Antineoplastic Agents
Aromatase Inhibitors
Steroid Synthesis Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Estrogen Antagonists
Hormone Antagonists
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs