Intrauterine insemination at 42 hours versus 36 hours after the hCG ovulation trigger
Interest of Sperm Insemination at 42 Hours Post hCG Compared to 36h in Intrauterine Insemination : a Randomized Controlled Trial. SYNcIU
This study will test whether doing IUI 42 hours instead of 36 hours after the hCG shot leads to more live births for people having intrauterine insemination for infertility.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 692 (estimated) |
| Ages | 18 Years to 43 Years |
| Sex | Female |
| Sponsor | University Hospital, Toulouse Academic / other |
| Locations | 4 sites (Bordeaux and 3 other locations) |
| Trial ID | NCT06804538 on ClinicalTrials.gov |
What this trial studies
This randomized superiority trial will compare timing of intrauterine insemination performed at 42–43 hours versus 36–37 hours after hCG ovulation trigger in people undergoing gonadotropin-stimulated cycles with a GnRH antagonist. Participants will receive standard ovarian stimulation, luteal phase progestin support, and insemination using partner or donor sperm according to local procedures, with only the timing of IUI differing between groups. The primary outcome is live birth rate per cycle, and centers across France will follow participants through pregnancy outcome. The trial will also record sperm origin and other cycle variables to explore whether timing effects differ by sperm source.
Who should consider this trial
Good fit: Women aged 18–43 with two patent fallopian tubes undergoing their first or second gonadotropin-stimulated IUI cycle with GnRH antagonist, using partner or donor sperm (prior migration test ≥1 million inseminable sperm), who meet local legal and consent requirements.
Not a fit: People with blocked tubes, severe male-factor infertility requiring IVF, those outside the age limits, or those needing treatments other than gonadotropin stimulation with GnRH antagonist are unlikely to benefit from this timing comparison.
Why it matters
Potential benefit: If successful, delaying IUI to about 42 hours after hCG could increase the chance of a live birth per cycle by better aligning egg maturity and sperm availability.
How similar studies have performed: Previous randomized trials have reported higher pregnancy rates with delayed IUI to around 42 hours, but this is the first trial designed to measure live birth as the primary outcome.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Single unmarried woman or heterosexual or homosexual couple in which the woman wishing to carry the pregnancy is aged 18 to 43 and the spouse is aged 18 to 60 at the time of inclusion * 2 permeable tubes for the woman receiving the insemination * Spouse's sperm (Number of inseminable sperm ≥ 1 million in prior survival migration test) or sperm donation * 1st or 2nd intrauterine insemination for this child project * Ovarian stimulation by gonadotropin with GnRH antagonist (introduced on a fixed day or according to the follicular size criterion of the center) * Luteal phase support with a progestin until at least the pregnancy test * Affiliation or beneficiary of a social security scheme or equivalent for both partners of the couple if applicable * Free and informed consent signed by the unmarried woman or both members of the couple * Couples and unmarried women meeting the conditions for access to PMA according to the French bioethics law Exclusion Criteria: * Endometriosis stage III or IV * History of ectopic pregnancy * ≥ 3 spontaneous miscarriages * Single woman or couple where one of the two partners (or both) is (are) under the protection of justice, under guardianship or under curatorship * Single woman or couple who have already participated in the study once * Single woman or couple participating in another interventional clinical study
Where this trial is running
Bordeaux and 3 other locations
- CHU Bordeaux — Bordeaux, France (Not_yet_recruiting)
- CHU La Réunion — La Réunion, France (Not_yet_recruiting)
- CHU Poitiers — Poitiers, France (Not_yet_recruiting)
- CHU Toulouse — Toulouse, France (Recruiting)
Study contacts
- Study coordinator: Jessika MOREAU, MD
- Email: moreau.je@chu-toulouse.fr
- Phone: 567771017
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.