Progesterone Supplementation After Letrozole-stimulated Insemination

NCT07508657 | Not Yet Recruiting Phase 4

• 2 other identifiers: 051120252025-524327-53-00
• Study Type: interventional
• Target: 690
• Locations: 1 country
• Sites: 4

Brief Summary

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:

• Vaginal progesterone from the day after insemination (Cyclogest 400 mg twice daily)
• No luteal phase support, reflecting current clinical practice 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.

Conditions

Infertility

Keywords

Luteal phase support; Intrauterine insemination; Letrozole; Vaginal progesterone; Randomized clinical trial; Ovulation induction

Outcome Measures

Primary Outcomes (1)

• Clinical Pregnancy Rate

  Defined as an ultrasonographically visible foetal heartbeat at 7-9 weeks of gestation

  Gestational age 7-9 weeks

Secondary Outcomes (7)

• Live Birth Rate

  At the time of delivery

• Biochemical Pregnancy Rate

  14-17 days after intrauterine insemination

• Early Pregnancy Loss

  Up to 10 weeks of gestation

• Fetal miscarriage

  From 10 weeks of gestation to delivery

• Obstetric outcomes

  At time of delivery

Study Arms (2)

Intervention

EXPERIMENTAL

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

Comparison

NO INTERVENTION

No luteal phase support will be administered after insemination, reflecting current standard treatment.

Interventions

Progesterone DRUG

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

Intervention

Eligibility Criteria

• Age: 18 Years - 37 Years
• Gender Eligibility Details: Participation is restricted to women of reproductive age with preserved ovarian and uterine function. Inclusion of men is therefore not applicable.
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18-37 years
• Scheduled for IUI with homologous or donor sperm
• Undergoing mild ovarian stimulation with letrozole
• Ability to provide written informed consent

You may not qualify if:

• Age \> 37 years
• Anovulation due to hypogonadotropic hypogonadism
• Known hypersensitivity to progesterone or hard fat listed as an excipient in the Summary of Product Characteristics (SmPC) for Cyclogest.
• Known or suspected progesterone-sensitive malignant tumours
• Porphyria
• Known missed abortion or ectopic pregnancy
• Active arterial or venous thromboembolism, severe thrombophlebitis, or a history of these conditions
• Severe hepatic dysfunction or liver disease
• Inability to speak or understand Danish sufficiently to comprehend oral and written study information

Sponsors & Collaborators

• Kirstine Kirkegaard: lead

Study Sites (4)

Copenhagen University Hospital - Rigshospitalet. Department of Gynecology, Fertility and Obstetrics

Copenhagen, 2100, Denmark

Location

The Fertility Clinic, Herlev Hospital

Herlev, 2730, Denmark

Location

University Clinic for Fertility, Horsens Regional Hospital, Central Denmark Region

Horsens, 8700, Denmark

Location

The Fertility Clinic, Hvidovre Hospital

Hvidovre, 2650, Denmark

Location

MeSH Terms

Conditions

Infertility

Interventions

Progesterone

Condition Hierarchy (Ancestors)

Genital Diseases; Urogenital Diseases

Intervention Hierarchy (Ancestors)

Pregnenediones; Pregnenes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Corpus Luteum Hormones; Gonadal Hormones; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Progesterone Congeners; Gonadal Steroid Hormones

Study Officials

• Kirstine Kirkegaard, Clinical Associate Professor

  University Clinic for Fertility, Horsens Regional Hospital, Central Denmark Region

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Kirstine Kirkegaard, Clinical Associate Professor

CONTACT

+4578426562; fertilitet@horsens.rm.dk

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Outcome assessment is performed by a physician masked to treatment allocation. Participants and treating clinical staff are not masked.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Clinical Associate Professor, MD, PhD

Study Record Dates

• First Submitted: March 27, 2026
• First Posted: April 2, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): June 1, 2029
• Study Completion (Estimated): January 1, 2030
• Last Updated: April 2, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

DK (4)