A Phase 4 interventional study of Progesterone in Infertility, sponsored by Kirstine Kirkegaard. Recruiting at 4 sites in Denmark. Open to female participants aged 18 Years to 37 Years. Per ClinicalTrials.gov, last updated 2026-09-09.
Sponsored by Kirstine Kirkegaard · Phase 4, Interventional, and Treatment
This trial aims to investigate whether luteal phase support improves the chance of pregnancy in women undergoing intrauterine insemination (IUI) following ovarian stimulation with letrozole.
In this randomized clinical trial, 690 women undergoing letrozole-stimulated IUI at four public fertility clinics in Denmark will be randomly allocated to one of two groups:
All participants will undergo a standard letrozole-stimulated IUI treatment, including ultrasound monitoring, ovulation triggering, and insemination. Blood samples will be collected on the day of insemination and 7-9 days after insemination to measure hormone levels.
The results of this trial will provide further insight into the role of progesterone support in letrozole-stimulated IUI cycles.
Exclusion Criteria:
Vaginal progesterone luteal phase support. Progesterone is administered as Cyclogest 400 mg twice daily form the day after insemination. Treatment is continued until gestational age 10 weeks in the event of clinical pregnancy, or until pregnancy is ruled out in women who do not achieve a clinical pregnancy.
Drug: Progesterone
No luteal phase support will be administered after insemination, reflecting current standard treatment.
Vaginal progesterone (Cyclogest) 400 mg administered twice daily starting the day after insemination. Treatment is continued until gestational age 10 weeks in the event of clinical pregnancy or until clinical pregnancy is ruled out.
Also known as: Cyclogest
Clinical Pregnancy Rate
Defined as an ultrasonographically visible foetal heartbeat at 7-9 weeks of gestation
Time frame: Gestational age 7-9 weeks
Live Birth Rate
Defined as the birth of one or more living infants after a pregnancy of GA ≥ 22 weeks
Time frame: At the time of delivery
Biochemical Pregnancy Rate
Defined as a positive serum or urine β-hCG test 14-17 days after intrauterine insemination
Time frame: 14-17 days after intrauterine insemination
Early Pregnancy Loss
Defined as intrauterine pregnancy loss before 10 weeks of gestational age
Time frame: Up to 10 weeks of gestation
Fetal miscarriage
Defined as pregnancy loss ≥ 10 weeks size with a fetus (≥ 33 mm) on ultrasound
Time frame: From 10 weeks of gestation to delivery
Obstetric outcomes
Obstetric complications including hypertensive disorders of pregnancy, gestational diabetes, postpartum hemorrhage and cesarean section
Time frame: At time of delivery
Perinatal outcomes
Preterm birth, birth weight, congenital malformations, and perinatal mortality (defined as foetal or neonatal death from GA 22+0 to 7 days after birth).
Time frame: At time of delivery
Hormone levels
Serum hormone levels measured on the day of insemination, in the mid-luteal phase and on the day of ovulation trigger (optional), including progesterone, estradiol, LH and FSH.
Time frame: Time of insemination and mid-luteal phase (approximately 7-9 days after insemination).
Plan to share: No — Individual participant data will not be made avaliable.
No publications or documents are linked to this record.
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