InfertilitySYNcIUNCT06804538
Interest of Sperm Insemination at 42 Hours Post hCG Compared to 36h in Intrauterine Insemination
A study testing Insemination between 42 and 43 hours post hCG and Insemination between 36 and 37 hours post hCG in people with Infertility and Intrauterine Insemination (IUI), run by University Hospital, Toulouse at 4 sites in France.
Trial summary
Intrauterine insemination (IUI) is a common therapeutic option to treate infertility. Typically performed 36 hours post-hCG injection to trigger ovulation. However, research suggests delaying IUI to 42 hours post-hCG may improve egg quality and sperm synchronization for fertilization, leading to higher pregnancy… Read more about this study
- Who is it for?
- Ages 18 to 43 years, women only
- Conditions the study is for
- Infertility, Intrauterine Insemination (IUI)
- What is being tested?
- Insemination between 42 and 43 hours post hCG and Insemination between 36 and 37 hours post hCG
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 692 participants
- Where
- 4 sitesFrance
- Study dates
- 9 Sep 2025to 1 Dec 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 43 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- 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
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- 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
Who cannot join
- 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
Trial locations and contacts
4 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Celia BETTIOL, CRA contact
France4 sites, 4 recruiting
- Not yet recruiting
CHU Bordeaux
Bordeaux
Lucie CHANSEL-DEBORDEAUX, MD, 05 56 79 56 81 ext. +33, lucie.chansel-debordeaux@chu-bordeaux.fr
Lucie Chansel Debordeaux, MD
- Not yet recruiting
CHU La Réunion
La Réunion
Joffrey MONS, MD, 02 62 35 95 19 ext. +33, joffrey.mons@chu-reunion.fr
Joffrey MONS, MD
- Not yet recruiting
CHU Poitiers
Poitiers
Stéphanie ROBERT BITAUDEAU, MD, 05.49.44.39.56 ext. +33, Stephanie.ROBERT-BITAUDEAU@chu-poitiers.fr
Stephanie ROBERT-BITAUDEAU, MD
- Recruiting
CHU Toulouse
Toulouse
Jessika MOREAU, MD, 567771017 ext. +33, moreau.je@chu-toulouse.fr
Jessika MOREAU, MD
About this study
Official title: Interest of Sperm Insemination at 42 Hours Post hCG Compared to 36h in Intrauterine Insemination : a Randomized Controlled Trial. SYNcIU
Intrauterine insemination (IUI) is a common therapeutic option to treate infertility. Typically performed 36 hours post-hCG injection to trigger ovulation. However, research suggests delaying IUI to 42 hours post-hCG may improve egg quality and sperm synchronization for fertilization, leading to higher pregnancy rates. A proposed superiority study aims to compare IUI timing at 36 hours versus 42 hours post-hCG injection to evaluate its impact on live birth rates. The primary objective is to assess the effectiveness (live birth rates) of IUI at two different post-hCG timing intervals (42-43 hours vs 36-37 hours).
Read the detailed description
Infertility is a major problem affecting approximately 15% of couples worldwide, with a notable increase due to various factors such as advanced maternal age and unhealthy lifestyles. Intrauterine insemination (IUI) is a common treatment option that aims to increase the chances of conception. It is preceded by ovarian stimulation to promote the growth of the follicles. Traditionally, IUI is performed 36 hours after an hCG injection to trigger ovulation, but research suggests benefits to delaying it. Studies have shown that delaying IUI to 42 hours post-hCG could improve oocyte quality and sperm synchronization for fertilization. Randomized clinical trials have shown higher pregnancy rates with delayed UTIs to 42 hours. We therefore propose a superiority study to compare IU at 36 hours and 42 hours post-hCG, taking into account the origin of the sperm used. This study will be the first to evaluate the effect of hCG-IU delay on live birth rates. In all centers, inseminations will be carried out according to the usual procedure. Patients in the experimental group will be stimulated by gonadotropins, ovulation will be blocked by a GnRH antagonist then triggered by hCG allowing IU to occur between 42 and 43 hours post hCG. These treatments are similar to the control group. Only the timing of the IUI compared to the timing of ovulation triggering is different. In the comparison group, ovulation will be triggered in order to carry out intrauterine insemination between 36 and 37 hours post hCG (as is already the case in clinical practice). Blinding is not possible for this study. On the other hand, the different endpoints will be evaluated without the randomization group being blinded by the evaluating gynaecologists. The monitoring of included patients is similar to the care pathway. The follow-up data (pregnancy test, pregnancy ultrasound, progress of the birth) will be carried out in the same way as the care (for which these data are necessarily collected)
- Conditions
- Infertility, Intrauterine Insemination (IUI)
- Being tested
- Insemination between 42 and 43 hours post hCG, Insemination between 36 and 37 hours post hCG
- Keywords
- intrauterine insemination, infertility, sperm donation, timing, live birth
- Medical subject headings
- Infertility
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Insemination between 42 and 43 hours post hCGProcedure or surgery
Patients will be stimulated by gonadotropins, ovulation will be blocked by a GnRH antagonist then triggered by hCG allowing IU to occur between 42 and 43 hours post hCG
Insemination between 36 and 37 hours post hCGProcedure or surgery
Patients will be stimulated with gonadotropin and GnRH antagonist whose ovulation will be triggered and for which intrauterine insemination will be carried out between 36 and 37 hours post hCG
| Study group | Role | What they receive |
|---|---|---|
| Experimental group: insemination between 42 and 43 hours post hCG | Experimental | Patients in the experimental group will be stimulated by gonadotropins, ovulation will be blocked by a GnRH antagonist then triggered by hCG allowing IU to occur between 42 and 43 hours post hCG. These treatments are similar to the control group. Only the timing of the IUI compared to the timing of ovulation triggering is different Receives: Procedure: Insemination between 42 and 43 hours post hCG |
| Control group: insemination between 36 and 37 hours post hCG | Active comparator | In the comparison group, patients will be stimulated with gonadotropin and GnRH antagonist whose ovulation will be triggered and for which intrauterine insemination will be carried out between 36 and 37 hours post hCG (as it is already the case in clinical practice). Receives: Procedure: Insemination between 36 and 37 hours post hCG |
What is being measured
The primary outcome is the main question the study is designed to answer.
Delivery rate after 22 weeks of pregnancy with at least one live birth per woman
The live birth rate is the most relevant clinical criterion for judging the effectiveness (success) of the IUI attempt. This criterion will be evaluated according to the usual procedures of the centers via the obligatory collection of post-ART childbirth data and transmission in a regulatory manner to the Biomedicine Agency.
Measured: the day of delivery
Secondary outcomes (3)
Biochemical pregnancy rate
Number of β-hCG >100 IU/l
Measured: The day of the pregnancy test: 15 days after insemination (T0)
Clinical pregnancy rate
Presence of at least one intrauterine gestational sac with fetal heart activity.
Measured: During ultrasound realised at 6 weeks' amenorrhea (SA)
Spontaneous miscarriage rate
Number of pregnancies terminated before 22 weeks of pregnancy/number of biochemical pregnancies
Measured: The day of delivery before 22 weeks of pregnancy
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Feb 2025
- Study start9 Sep 2025
- Primary completion1 Dec 2028 (estimated)
- Study completion1 Dec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for InfertilityStudies of the same condition, open and under way.
- More trials run by University Hospital, ToulouseThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 692 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Hospital, Toulouse
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06804538
- Sponsor's protocol ID
- RC31/24/0309
- Acronym
- SYNcIU
- Status last verified
- Sep 2025
- First submitted
- 9 Jan 2025
- Last updated
- 5 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 5 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Interest of Sperm Insemination at 42 Hours Post hCG Compared to 36h in Intrauterine Insemination : a Randomized Controlled Trial. SYNcIU
- ClinicalTrials.gov ID
- NCT06804538
- Acronym / sponsor ID
- SYNcIU / RC31/24/0309
- Conditions
- Infertility, Intrauterine Insemination (IUI)
- Keywords
- intrauterine insemination, infertility, sperm donation, timing, live birth
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 692 participants (estimated)
- Lead sponsor
- University Hospital, ToulouseUniversity, hospital or other
- Study start
- 9 Sep 2025 (actual)
- Primary completion
- 1 Dec 2028 (estimated)
- Study completion
- 1 Dec 2028 (estimated)
- First posted
- 3 Feb 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Intrauterine insemination (IUI) is a common therapeutic option to treate infertility. Typically performed 36 hours post-hCG injection to trigger ovulation. However, research suggests delaying IUI to 42 hours post-hCG may improve egg quality and sperm synchronization for fertilization, leading to higher pregnancy rates. A proposed superiority study aims to compare IUI timing at 36 hours versus 42 hours post-hCG injection to evaluate its impact on live birth rates. The primary objective is to assess the effectiveness (live birth rates) of IUI at two different post-hCG timing intervals (42-43 hours vs 36-37 hours).
Detailed description
Infertility is a major problem affecting approximately 15% of couples worldwide, with a notable increase due to various factors such as advanced maternal age and unhealthy lifestyles. Intrauterine insemination (IUI) is a common treatment option that aims to increase the chances of conception. It is preceded by ovarian stimulation to promote the growth of the follicles. Traditionally, IUI is performed 36 hours after an hCG injection to trigger ovulation, but research suggests benefits to delaying it. Studies have shown that delaying IUI to 42 hours post-hCG could improve oocyte quality and sperm synchronization for fertilization. Randomized clinical trials have shown higher pregnancy rates with delayed UTIs to 42 hours. We therefore propose a superiority study to compare IU at 36 hours and 42 hours post-hCG, taking into account the origin of the sperm used. This study will be the first to evaluate the effect of hCG-IU delay on live birth rates. In all centers, inseminations will be carried out according to the usual procedure. Patients in the experimental group will be stimulated by gonadotropins, ovulation will be blocked by a GnRH antagonist then triggered by hCG allowing IU to occur between 42 and 43 hours post hCG. These treatments are similar to the control group. Only the timing of the IUI compared to the timing of ovulation triggering is different. In the comparison group, ovulation will be triggered in order to carry out intrauterine insemination between 36 and 37 hours post hCG (as is already the case in clinical practice). Blinding is not possible for this study. On the other hand, the different endpoints will be evaluated without the randomization group being blinded by the evaluating gynaecologists. The monitoring of included patients is similar to the care pathway. The follow-up data (pregnancy test, pregnancy ultrasound, progress of the birth) will be carried out in the same way as the care (for which these data are necessarily collected)
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Experimental group: insemination between 42 and 43 hours post hCG | Experimental | Procedure: Insemination between 42 and 43 hours post hCGPatients in the experimental group will be stimulated by gonadotropins, ovulation will be blocked by a GnRH antagonist then triggered by hCG allowing IU to occur between 42 and 43 hours post hCG. These treatments are similar to the control group. Only the timing of the IUI compared to the timing of ovulation triggering is different |
| Control group: insemination between 36 and 37 hours post hCG | Active comparator | Procedure: Insemination between 36 and 37 hours post hCGIn the comparison group, patients will be stimulated with gonadotropin and GnRH antagonist whose ovulation will be triggered and for which intrauterine insemination will be carried out between 36 and 37 hours post hCG (as it is already the case in clinical practice). |
Who may qualify
- Ages
- 18 to 43 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (9 listed)
- 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)
Key exclusion criteria (6 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Insemination between 42 and 43 hours post hCGPatients will be stimulated by gonadotropins, ovulation will be blocked by a GnRH antagonist then triggered by hCG allowing IU to occur between 42 and 43 hours post hCG | Procedure or surgery | Experimental group: insemination between 42 and 43 hours post hCG |
| Insemination between 36 and 37 hours post hCGPatients will be stimulated with gonadotropin and GnRH antagonist whose ovulation will be triggered and for which intrauterine insemination will be carried out between 36 and 37 hours post hCG | Procedure or surgery | Control group: insemination between 36 and 37 hours post hCG |
Primary outcome
Delivery rate after 22 weeks of pregnancy with at least one live birth per woman
Time frame: the day of delivery
The live birth rate is the most relevant clinical criterion for judging the effectiveness (success) of the IUI attempt. This criterion will be evaluated according to the usual procedures of the centers via the obligatory collection of post-ART childbirth data and transmission in a regulatory manner to the Biomedicine Agency.
3 secondary outcomes
Biochemical pregnancy rate
Time frame: The day of the pregnancy test: 15 days after insemination (T0)
Clinical pregnancy rate
Time frame: During ultrasound realised at 6 weeks' amenorrhea (SA)
Spontaneous miscarriage rate
Time frame: The day of delivery before 22 weeks of pregnancy
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 May 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Celia BETTIOL, CRA contact
4 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Insemination between 42 and 43 hours post hCG and Insemination between 36 and 37 hours post hCG in people with Infertility and Intrauterine Insemination (IUI), run by University Hospital, Toulouse at 4 sites in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 5 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Jessika MOREAU, MD (567771017 ext. +33, moreau.je@chu-toulouse.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Delivery rate after 22 weeks of pregnancy with at least one live birth per woman (time frame: the day of delivery). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 May 2026.