Mannose-Binding Lectin DeficiencyNCT05169541
Association Between Plasma Level of Mannose Binding Lectin and Human Reproduction
An observational study of Mannose-Binding Lectin Deficiency and Recurrent Pregnancy Loss, run by Aalborg University Hospital at 1 site in Denmark.
Trial summary
A low plasma level of mannose binding lectin (p-MBL) is associated with unexplained recurrent pregnancy loss (RPL), but it is not investigated if it is associated with unexplained reproductive failure in general, including recurrent implantation failure (RIF) after assisted reproductive technology (ART) (including… Read more about this study
- Who is it for?
- Ages 18 to 41 years, women only
- Conditions the study is for
- Mannose-Binding Lectin Deficiency, Recurrent Pregnancy Loss, Recurrent Implantation Failure
- Type of treatment
- Injection or infusion
- How many people
- 500 participants
- Where
- 1 siteDenmark
- Study dates
- 1 Jan 2016to 30 Nov 2026
- Phase
- Observational
- 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 41 years
- Women only
- Adult
Study population: Danish female population. The centers cover mainly the western region of Denmark, but patients from all over Denmark can be treated at each center. The Aagaard Klinik is a private IVF clinic and therefore their patients pay for their ART treatments. Patients contact the clinic themself when they need medical support because of reproductive failure. The RPL center at AaUH (public hospital) is available without costs for the patient. Patients are referred from their practitioner or fertility clinic or gynecologist when they have experienced 3 or more pregnancy losses (including biochemical and clinical pregnancies).
Who may be able to join
- fulfil one of the following:
- 3 consecutive pregnancy losses after spontaneous conception
- 3 consecutive pregnancy losses after assisted reproductive technology treatment (ART) including IVF, ICSI and FET
- 3 failed embryo transfers characterized by no achieved pregnancy (after 3 cycles with minimum 1 embryo transfer of a good-quality embryo in each cycle.)
Who cannot join
- Age <18 or >45 years
- AMH <4.0 pmol/l unless donor egg in previous cycles
- Significant uterine malformation
- Known endometrial pathologies including intrauterine endometriosis, adenomyosis, hyperplasia or polyps
- Known chromosomal abnormalities
- Pregnancy >9 weeks of gestation at the time collecting the blood sample
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Ole B. Christiansen contact
Denmark1 site, 1 recruiting
- Recruiting
Aagaard Klinik
Aarhus, 8200
Aboubakar Cissé, MD, +45 86 12 61 21
About this study
Official title: Is Plasma Level of Mannose Binding Lectin Associated With Reproductive Failure?
A low plasma level of mannose binding lectin (p-MBL) is associated with unexplained recurrent pregnancy loss (RPL), but it is not investigated if it is associated with unexplained reproductive failure in general, including recurrent implantation failure (RIF) after assisted reproductive technology (ART) (including IVF, ICSI and FET), recurrent pregnancy loss (RPL) after spontaneous conception, and RPL after ART.
Read the detailed description
The prevalence of a low p-MBL level is higher in patients with unexplained RPL than in the background population, while a high level is significantly less frequent in RPL patients (Nørgaard-Pedersen et al., submitted).
Approximately 50% of RPL patients have none of the evidence-based risk factors associated with RPL. Unexplained RPL is more complicated since finding the cause is essential for offering the optimal intervention to improve the patient's chances of a child.
Other conditions characterized by reproductive failure are infertility and recurrent implantation failure (RIF). The underlying mechanisms and the physiologic stage in early pregnancy being complicated and impeding normal pregnancy may probably differ between these pathologic conditions, since theoretically RIF would involve complicated embryo apposition, adhesion and invasion and clinical/visualized pregnancy losses would involve complicated stages later in the implantation process and fetal development. However, these conditions are suggested to have partly overlapping causes since most of the evidence-based risk factor recur; including parental chromosomal abnormalities, and maternal endocrine disorders, acquired thrombophilia, anatomic abnormalities in the uterine cavity, and endometrial and ovarian diseases. In addition, adverse immune responses against the embryo have been suggested as a cause of reproductive failure. If RPL is associated with a low p-MBL level, RIF may be so too.
The investigators aim to explore the p-MBL level in patients suffering from reproductive failure.
If low p-MBL level is associated with all the investigated subgroups of patients suffering from reproductive failure, this would strengthen our theory that MBL is involved in the pathophysiology characterized by reproductive failure in the very early stages of pregnancy and should therefore take part in the exploration of all patients with reproductive failure.
- Conditions
- Mannose-Binding Lectin Deficiency, Recurrent Pregnancy Loss, Recurrent Implantation Failure, Infertility, Habitual Abortion, Recurrent Miscarriage
- Medical subject headings
- Mannose-Binding Protein Deficiency, Infertility, Abortion, Habitual, Abortion, Spontaneous
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Recurrent pregnancy loss after spontaneous conception | Minimum three consecutive losses from pregnancies achieved after spontaneous conception | |
| Recurrent pregnancy loss after assisted reproductive treatment | Minimum three consecutive losses from pregnancies achieved after assisted reproductive treatment (ART), which includes in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and frozen embryo transfer (FER). | |
| Recurrent implantation failure | Minimum three consecutive embryo transfers (ET) of good quality embryos with no hCG production. The patient must not have experienced any clinical pregnancies (i.e. evidence of pregnancy on an US or by histopathological examination) after IVF or spontaneous conception. Biochemical pregnancies after spontaneous conception, which terminated before evidence of a gestational sac on an ultrasonic scan (US) could be visualized and before the series of RIF occurred, are accepted. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Low p-MBL level
Low plasma mannose binding lectin level defined as <500 ug/l
Measured: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
Very low p-MBL level
Very low plasma mannose binding lectin level defined as <100 ug/l
Measured: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
High p-MBL level
High plasma mannose binding lectin level defined as >3000 ug/l
Measured: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
Secondary outcomes (1)
Odds ratio for a low p-MBL level
Comparing prevalence in the patient group with danish female background population (n=185)
Measured: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Dec 2021
- Study start1 Jan 2016
- Primary completion30 Nov 2026 (estimated)
- Study completion30 Nov 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Mannose-Binding Lectin DeficiencyStudies of the same condition, open and under way.
- More trials run by Aalborg University HospitalThe 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
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 500 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Aalborg University Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Caroline Nørgaard-Pedersen, Aalborg University Hospital
- Investigators
- Caroline Nørgaard-Pedersen, M.D., Principal investigator, Aalborg University Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05169541
- Sponsor's protocol ID
- MBL_reproduction_2022
- Status last verified
- Oct 2025
- First submitted
- 19 Dec 2021
- Last updated
- 24 Nov 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Data obtained through this study may be provided to qualified researchers with academic interest in RPL after approval by the researchers. Data will be coded with no personal identifiers included. Approval of the request and execution of all applicable agreements (i.e. a material transfer agreement) are prerequisites to the sharing of data with the requesting party. Please contact the primary researcher. The researchers maintain the right to reject the request. Data requests can be submitted starting 12 months after article publication.
Study at a glance
From the registry record, last updated by the sponsor on 24 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Is Plasma Level of Mannose Binding Lectin Associated With Reproductive Failure?
- ClinicalTrials.gov ID
- NCT05169541
- Acronym / sponsor ID
- MBL_reproduction_2022
- Conditions
- Mannose-Binding Lectin Deficiency, Recurrent Pregnancy Loss, Recurrent Implantation Failure, Infertility, Habitual Abortion, Recurrent Miscarriage
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 500 participants (estimated)
- Lead sponsor
- Aalborg University HospitalUniversity, hospital or other
- Study start
- 1 Jan 2016 (actual)
- Primary completion
- 30 Nov 2026 (estimated)
- Study completion
- 30 Nov 2026 (estimated)
- First posted
- 27 Dec 2021 (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.
A low plasma level of mannose binding lectin (p-MBL) is associated with unexplained recurrent pregnancy loss (RPL), but it is not investigated if it is associated with unexplained reproductive failure in general, including recurrent implantation failure (RIF) after assisted reproductive technology (ART) (including IVF, ICSI and FET), recurrent pregnancy loss (RPL) after spontaneous conception, and RPL after ART.
Detailed description
The prevalence of a low p-MBL level is higher in patients with unexplained RPL than in the background population, while a high level is significantly less frequent in RPL patients (Nørgaard-Pedersen et al., submitted).
Approximately 50% of RPL patients have none of the evidence-based risk factors associated with RPL. Unexplained RPL is more complicated since finding the cause is essential for offering the optimal intervention to improve the patient's chances of a child.
Other conditions characterized by reproductive failure are infertility and recurrent implantation failure (RIF). The underlying mechanisms and the physiologic stage in early pregnancy being complicated and impeding normal pregnancy may probably differ between these pathologic conditions, since theoretically RIF would involve complicated embryo apposition, adhesion and invasion and clinical/visualized pregnancy losses would involve complicated stages later in the implantation process and fetal development. However, these conditions are suggested to have partly overlapping causes since most of the evidence-based risk factor recur; including parental chromosomal abnormalities, and maternal endocrine disorders, acquired thrombophilia, anatomic abnormalities in the uterine cavity, and endometrial and ovarian diseases. In addition, adverse immune responses against the embryo have been suggested as a cause of reproductive failure. If RPL is associated with a low p-MBL level, RIF may be so too.
The investigators aim to explore the p-MBL level in patients suffering from reproductive failure.
If low p-MBL level is associated with all the investigated subgroups of patients suffering from reproductive failure, this would strengthen our theory that MBL is involved in the pathophysiology characterized by reproductive failure in the very early stages of pregnancy and should therefore take part in the exploration of all patients with reproductive failure.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Recurrent pregnancy loss after spontaneous conception | – | –Minimum three consecutive losses from pregnancies achieved after spontaneous conception |
| Recurrent pregnancy loss after assisted reproductive treatment | – | –Minimum three consecutive losses from pregnancies achieved after assisted reproductive treatment (ART), which includes in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and frozen embryo transfer (FER). |
| Recurrent implantation failure | – | –Minimum three consecutive embryo transfers (ET) of good quality embryos with no hCG production. The patient must not have experienced any clinical pregnancies (i.e. evidence of pregnancy on an US or by histopathological examination) after IVF or spontaneous conception. Biochemical pregnancies after spontaneous conception, which terminated before evidence of a gestational sac on an ultrasonic scan (US) could be visualized and before the series of RIF occurred, are accepted. |
Who may qualify
- Ages
- 18 to 41 years
- Sex
- Female only
- Age groups
- Adult
- Study population
- Danish female population. The centers cover mainly the western region of Denmark, but patients from all over Denmark can be treated at each center. The Aagaard Klinik is a private IVF clinic and therefore their patients pay for their ART treatments. Patients contact the clinic themself when they need medical support because of reproductive failure. The RPL center at AaUH (public hospital) is available without costs for the patient. Patients are referred from their practitioner or fertility clinic or gynecologist when they have experienced 3 or more pregnancy losses (including biochemical and clinical pregnancies).
Key inclusion criteria (4 listed)
- 3 consecutive pregnancy losses after spontaneous conception
- 3 consecutive pregnancy losses after assisted reproductive technology treatment (ART) including IVF, ICSI and FET
- 3 failed embryo transfers characterized by no achieved pregnancy (after 3 cycles with minimum 1 embryo transfer of a good-quality embryo in each cycle.)
Key exclusion criteria (6 listed)
- Age <18 or >45 years
- AMH <4.0 pmol/l unless donor egg in previous cycles
- Significant uterine malformation
- Known endometrial pathologies including intrauterine endometriosis, adenomyosis, hyperplasia or polyps
- Known chromosomal abnormalities
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Low p-MBL level
Time frame: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
Low plasma mannose binding lectin level defined as <500 ug/l
Very low p-MBL level
Time frame: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
Very low plasma mannose binding lectin level defined as <100 ug/l
High p-MBL level
Time frame: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
High plasma mannose binding lectin level defined as >3000 ug/l
1 secondary outcome
Odds ratio for a low p-MBL level
Time frame: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.
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 24 Nov 2025.
- Individual participant dataSharing planned: Yes. Data obtained through this study may be provided to qualified researchers with academic interest in RPL after approval by the researchers. Data will be coded with no personal identifiers included. Approval of the request and execution of all applicable agreements (i.e. a material transfer agreement) are prerequisites to the sharing of data with the requesting party. Please contact the primary researcher. The researchers maintain the right to reject the request. Data requests can be submitted starting 12 months after article publication.
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.
Ole B. Christiansen contact
Caroline Nørgaard-Pedersen, M.D. principal investigator
Aalborg University Hospital
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 Mannose-Binding Lectin Deficiency and Recurrent Pregnancy Loss, run by Aalborg University Hospital at 1 site in Denmark.
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 4 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 24 Nov 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 Denmark. 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 Caroline Noergaard-Pedersen, M.D. (+4541120267, c.noergaardpedersen@rn.dk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Low p-MBL level (time frame: Blood sample collected after admission when the patient is not pregnant or <9 weeks of gestation.). The study lists 3 primary outcomes in all. 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 24 Nov 2025.