Fertility DisordersNCT06128395
ASA 81 mg vs 162 mg During Frozen Embryo Transfer (FET)
An observational study of Fertility Disorders, run by Clinique Ovo at 1 site in Canada.
Trial summary
The use of low dose aspirin is recommended for high risk patients to reduce the risk of pre-eclampsia, placental abruption and antepartum hemorrhage. Recent studies have shown that in a specific population, the use of low dose aspirin might reduce the risk of preterm birth in pregnant women with singleton pregnancy. Read more about this study
- Who is it for?
- Ages Up to 40 years, women only
- Conditions the study is for
- Fertility Disorders
- What is being tested?
- Frozen embryo transfer
- How many people
- 1,207 participants
- Where
- 1 siteCanada
- Study dates
- 1 Nov 2023to 18 Sep 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
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 Up to 40 years
- Women only
- Child, Adult
Study population: FET Data spreadsheet from January 2022 to December 2022
Who may be able to join
- Women taking aspirin 81 mg or 162 mg prior to an autologous embryo transfer
- Age < 40 years old
- Embryo transfer cycle done at clinique ovo
Who cannot join
- Egg or embryo recipient
- History of recurrent miscarriages, defined as ≥ 3 consecutive losses
- Patients that needed Viagra, PRP or other modalities to improve their endometrial thickness
- Uterine factor infertility
- Abnormal hormonal profiles
- Stimulated embryo transfer cycles
- History of recurrent implantation failure defined as failed ≥ 2 euploid embryos transfer or ≥ 3 blastocysts
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Retrospective Study to Assess if Aspirin 162 mg is Better Than 81 mg for Embryo Transfer Outcomes
The use of low dose aspirin is recommended for high risk patients to reduce the risk of pre-eclampsia, placental abruption and antepartum hemorrhage. Recent studies have shown that in a specific population, the use of low dose aspirin might reduce the risk of preterm birth in pregnant women with singleton pregnancy. In June 2022, clinique ovo started implementing the use of Aspirin 162 mg instead of 81 mg in the frozen embryo transfer cycles based on recent study outcomes. The use of Aspirin 162 mg might have additional benefits on the embryo transfer outcomes by decreasing the miscarriage. Moreover this can be continued until late in pregnancy without adverse effects.
- Conditions
- Fertility Disorders
- Being tested
- Frozen embryo transfer
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Frozen embryo transferOther
A frozen embryo transfer involves thawing a fertilized embryo and transferring it in the uterus in order to obtain a pregnancy
| Study group | Role | What they receive |
|---|---|---|
| Aspirin 81 mg for Frozen Embryo Transfer (FET) | Subjects were prescribed Aspirin 81 mg to be started on the third day of their menstrual cycle in preparation for their FET. Receives: Other: Frozen embryo transfer | |
| Aspirin 162 mg for Frozen Embryo Transfer (FET) | Subjects were prescribed Aspirin 162 mg to be started on the third day of their menstrual cycle in preparation for their FET Receives: Other: Frozen embryo transfer |
What is being measured
The primary outcome is the main question the study is designed to answer.
Compare clinical pregnancy rate between patients prescribed Aspirin 81 mg vs Aspirin 162 mg
clinical pregnancy is the presence of fetal heartbeat at the viability ultrasound
Measured: Time Frame: 6 to 8 weeks after Frozen Embryo Transfer
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Nov 2023
- Study start1 Nov 2023
- Primary completion30 Aug 2024
- Study completion18 Sep 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Fertility DisordersStudies of the same condition, open and under way.
- 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
- Observational
- Observational model
- Cohort
- Time perspective
- Retrospective
- Enrolment
- 1,207 participants (actual)
Sponsor and investigators
- Lead sponsor
- Clinique Ovo
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Wael Jamal, MD, Principal investigator, Clinique Ovo
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06128395
- Sponsor's protocol ID
- 3384
- Status last verified
- Dec 2025
- First submitted
- 7 Nov 2023
- Last updated
- 9 Dec 2025
- 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 9 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Retrospective Study to Assess if Aspirin 162 mg is Better Than 81 mg for Embryo Transfer Outcomes
- ClinicalTrials.gov ID
- NCT06128395
- Acronym / sponsor ID
- 3384
- Conditions
- Fertility Disorders
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 1,207 participants (actual)
- Lead sponsor
- Clinique OvoIndustry (pharma, biotech, devices)
- Study start
- 1 Nov 2023 (actual)
- Primary completion
- 30 Aug 2024 (actual)
- Study completion
- 18 Sep 2024 (actual)
- First posted
- 13 Nov 2023 (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.
The use of low dose aspirin is recommended for high risk patients to reduce the risk of pre-eclampsia, placental abruption and antepartum hemorrhage. Recent studies have shown that in a specific population, the use of low dose aspirin might reduce the risk of preterm birth in pregnant women with singleton pregnancy. In June 2022, clinique ovo started implementing the use of Aspirin 162 mg instead of 81 mg in the frozen embryo transfer cycles based on recent study outcomes. The use of Aspirin 162 mg might have additional benefits on the embryo transfer outcomes by decreasing the miscarriage. Moreover this can be continued until late in pregnancy without adverse effects.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Aspirin 81 mg for Frozen Embryo Transfer (FET) | – | Other: Frozen embryo transferSubjects were prescribed Aspirin 81 mg to be started on the third day of their menstrual cycle in preparation for their FET. |
| Aspirin 162 mg for Frozen Embryo Transfer (FET) | – | Other: Frozen embryo transferSubjects were prescribed Aspirin 162 mg to be started on the third day of their menstrual cycle in preparation for their FET |
Who may qualify
- Ages
- Up to 40 years
- Sex
- Female only
- Age groups
- Child, Adult
- Study population
- FET Data spreadsheet from January 2022 to December 2022
Key inclusion criteria (3 listed)
- Women taking aspirin 81 mg or 162 mg prior to an autologous embryo transfer
- Age < 40 years old
- Embryo transfer cycle done at clinique ovo
Key exclusion criteria (7 listed)
- Egg or embryo recipient
- History of recurrent miscarriages, defined as ≥ 3 consecutive losses
- Patients that needed Viagra, PRP or other modalities to improve their endometrial thickness
- Uterine factor infertility
- Abnormal hormonal profiles
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 |
|---|---|---|
| Frozen embryo transferA frozen embryo transfer involves thawing a fertilized embryo and transferring it in the uterus in order to obtain a pregnancy | Other | Aspirin 162 mg for Frozen Embryo Transfer (FET), Aspirin 81 mg for Frozen Embryo Transfer (FET) |
Primary outcome
Compare clinical pregnancy rate between patients prescribed Aspirin 81 mg vs Aspirin 162 mg
Time frame: Time Frame: 6 to 8 weeks after Frozen Embryo Transfer
clinical pregnancy is the presence of fetal heartbeat at the viability ultrasound
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Dec 2025.
- 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. This study is not recruiting at the moment.
Wael Jamal, MD principal investigator
Clinique Ovo
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Fertility Disorders, run by Clinique Ovo at 1 site in Canada.
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 3 inclusion and 7 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: finished, as of the sponsor's last update on 9 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Compare clinical pregnancy rate between patients prescribed Aspirin 81 mg vs Aspirin 162 mg (time frame: Time Frame: 6 to 8 weeks after Frozen Embryo Transfer). 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 9 Dec 2025.