A Phase 2 interventional study of Letrozole 5 mg in IVF, sponsored by Nicholas Macklon. Completed at 2 sites in Denmark. Open to female participants aged 18 Years to 35 Years. Per ClinicalTrials.gov, last updated 2021-01-14.
Sponsored by Nicholas Macklon · Phase 2, Interventional, and Treatment
The goal of the randomised controlled study (RCT) is to identify novel strategies that can improve the luteal phase endocrinology after ovarian stimulation, with the aim of using less or no luteal support in IVF while making the endometrium thinner and more receptive to embryo implantation.
The high estradiol levels generated in IVF by multiple dominant follicles at the follicular-luteal phase transition generate powerful negative feedback at the pituitary gland, effectively switching off gonadotropin production. Without stimulation by endogenous luteinizing hormone (LH), the corpora lutea undergo involution and menstruation follows, preventing the establishment of pregnancy.
To address these detrimental effects of ovarian stimulation, the investigators will do a RCT with the use of aromatase inhibitors, which suppress the conversion of androgens to estrogens to ameliorate the unwanted effects of high estrogens.
This study is designed to test the hypothesis that preventing supra-physiological estrogen levels during ovarian stimulation restricts pituitary suppression sufficiently to allow LH levels to rise and support the corpora lutea, leading to a normal post-ovulatory luteal phase, evidenced by a normal duration and luteal phase endocrine profile. To test this, consenting oocyte donors will be randomized to receive co-treatment with aromatase inhibitors or no co-treatment during ovarian stimulation. Following oocyte retrieval, no luteal support will be provided to donors in both Groups.
This is the only study on the registry with Nicholas Macklon as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Exclusion of patients after earlier inclusion in the study in case of
In case of exclusion of a patient after earlier inclusion in the study, a new patient will be included.
recFSH and co-treatment with letrozole 5 mg/day from stimulation day 1 on cycle day 2 or 3 until the day before gonadotrophin releasing hormone(GnRH) agonist administration to trigger final oocyte maturation. GnRH antagonist 0.25 mg/day from stimulation day 5 until day of GnRH agonist administration. No luteal phase support.
Drug: Letrozole 5 mg
recFSH from stimulation day 1 on cycle day 2 or 3 until the day before GnRH agonist administration to trigger final oocyte maturation. GnRH antagonist 0.25 mg/day from stimulation day 5 until day of GnRH agonist administration. No luteal phase support.
recFSH and co-treatment with letrozole 5 mg/day from stimulation day 1 on cycle day 2 or 3 until the day before GnRH agonist administration to trigger final oocyte maturation. GnRH antagonist 0.25 mg/day from stimulation day 5 until day of GnRH agonist administration. No luteal phase support.
Also known as: Aromatase inhibitor
Length of luteal phase (days from aspiration untill bleeding)
Difference in lengths of days until bleeding (from aspiration until first day of bleeding) of the luteal phase between intervention group and control group.
Time frame: Up to three weeks
Phase of endometrial receptivity according to Endometrial Receptivity Array (ERA) test
Difference in established endometrial tissue and secretion markers of endometrial receptivity between intervention group and controls (genomic profile assessed by ERA test).
Time frame: ERA-test is taken 5 days after aspiration of oocytes.
Estradiol (E2),progesterone (P), luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels.
Differences in the area under the curve for plasma E2, P, LH and FSH levels from day of OPU until day 14 post OPU between intervention group and control group.
Time frame: Blood samples are taken on 1 day of oocyte aspiration, 2 days after, 5 days after and 14 days after.
Endometrium thickness.
Difference in endometrium thickness 5 days post oocyte pick-up (OPU) between intervention group and controls.
Time frame: Endometrium thickness is measured on 1 day of oocyte aspiration, 2 days after and 5 days after.
Plan to share: No
This study is completed, as verified in Jan 2021. You cannot join it, but the record below documents what was studied.
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