Gestational Diabetes Mellitus (GDM)BARI-GDMNCT07517406
Glycemic Markers for Predicting Gestational Diabetes in Pregnant Women With Previous Bariatric Surgery
An observational study of Gestational Diabetes Mellitus (GDM) and Pregnancy Complications, run by Burak Deniz Aydoğdu at 1 site in Turkey (Türkiye).
Trial summary
Gestational diabetes mellitus (GDM) is associated with significant maternal and fetal complications. The standard diagnostic test for GDM is the 75-gram oral glucose tolerance test (OGTT). Read more about this study
- Who is it for?
- Ages 18 to 50 years, women only
- Conditions the study is for
- Gestational Diabetes Mellitus (GDM), Pregnancy Complications, History of Bariatric Surgery
- Type of treatment
- Pill or oral medicine
- How many people
- 84 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Feb 2026to Dec 2027
- How long will I take part?
- 9 Months
- 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 50 years
- Women only
- No healthy volunteers
- Adult
Study population: The study population consists of pregnant women aged 18-50 years with a history of bariatric surgery prior to conception who were followed at the Department of Obstetrics and Gynecology of Prof. Dr. Cemil Taşcıoğlu City Hospital. Eligible participants have documented glycemic parameters during the first and/or second trimester (including fasting plasma glucose, HbA1c, urine glucose and/or oral glucose tolerance test results) and available third trimester and/or delivery records. Only singleton pregnancies with complete clinical data are included.
Who may be able to join
- Pregnant women aged 18-50 years
- Singleton pregnancy
- History of bariatric surgery prior to pregnancy
- Followed at Prof. Dr. Cemil Taşcıoğlu City Hospital, Department of Obstetrics and Gynecology
- Availability of glycemic parameters during early pregnancy (≤14 weeks) and/or between 24 and 28 weeks of gestation (fasting plasma glucose, HbA1c, urine glucose, and/or OGTT results if tolerated)
- Availability of sonographic and clinical follow-up data between 28 weeks of gestation and delivery (up to 40 weeks) Exclusion Criteria
Show all 10Show fewer
- Age <18 years or >50 years
- Multiple pregnancy
- Presence of known chronic systemic disease (e.g., pregestational diabetes or endocrine disorders)
- Incomplete or missing clinical data
Who cannot join
None listed.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site, 1 recruiting
- Recruiting
Prof. Dr. Cemil Taşcıoğlu City Hospital
Istanbul, Şişli, 34384
Burak Deniz AYDOĞDU, MD, 90 539-618-22-28, burakd.1992@hotmail.com
About this study
Official title: Predictive Value of Glycemic Markers for Gestational Diabetes Mellitus and Pregnancy Complications in Pregnant Women With Prior Bariatric Surgery Who Cannot Tolerate Oral Glucose Tolerance Testing
Gestational diabetes mellitus (GDM) is associated with significant maternal and fetal complications. The standard diagnostic test for GDM is the 75-gram oral glucose tolerance test (OGTT). However, pregnant women who have undergone bariatric surgery may not tolerate OGTT due to dumping syndrome and gastrointestinal side effects. This creates diagnostic challenges in this specific population.
The aim of this prospective observational study is to evaluate whether routinely measured glycemic markers, including fasting blood glucose, postprandial blood glucose, HbA1c, and urinary glucose levels, can predict the development of gestational diabetes mellitus and related pregnancy complications in women with prior bariatric surgery.
Read more
Pregnant women aged 18-50 years with a history of bariatric surgery will be enrolled and followed throughout pregnancy. The predictive value of glycemic markers for GDM, macrosomia, and polyhydramnios will be analyzed using multivariable logistic regression models.
This study aims to provide alternative diagnostic approaches for GDM screening in pregnant women who are unable to tolerate OGTT and to contribute to improving maternal and perinatal outcomes in this growing patient population.
Read the detailed description
Gestational diabetes mellitus (GDM) is a common pregnancy complication associated with increased risks of maternal and perinatal morbidity. Early identification and appropriate management are essential to reduce adverse outcomes such as macrosomia, polyhydramnios, and cesarean delivery.
The standard diagnostic approach for GDM is the 75-gram oral glucose tolerance test (OGTT). However, women with prior bariatric surgery frequently experience intolerance to glucose loading due to dumping syndrome, which limits the reliability and feasibility of OGTT in this population. Consequently, alternative diagnostic strategies are required.
This prospective observational cohort study will be conducted at Prof. Dr. Cemil Taşcıoğlu City Hospital between February 2026 and December 2027. Pregnant women aged 18-50 years with a history of bariatric surgery will be enrolled during the first or second trimester. Participants will be categorized according to OGTT tolerance (tolerated vs. not tolerated/refused).
Baseline demographic characteristics including maternal age, gravidity, parity, obstetric history, and educational status will be recorded. Glycemic parameters assessed during routine antenatal follow-up will include fasting plasma glucose, postprandial glucose, HbA1c levels, and urinary glucose measurements. Second and third trimester ultrasound findings will be documented. Pregnancy outcomes including diagnosis of GDM, macrosomia (birth weight >4000 g), and polyhydramnios will be recorded.
The primary objective is to evaluate the predictive value of routine glycemic markers for GDM. Secondary objectives include assessing their association with macrosomia and polyhydramnios.
Statistical analyses will be performed using SPSS version 27. Continuous variables will be summarized as mean ± standard deviation or median (interquartile range) depending on distribution. Comparisons between groups will be performed using the Mann-Whitney U test. Multivariable logistic regression models will be used to determine independent predictors of GDM and other pregnancy complications after adjustment for potential confounders.
This study aims to provide evidence for alternative screening approaches in pregnant women with prior bariatric surgery who are unable to tolerate OGTT and to improve clinical decision-making in this growing patient population.
- Conditions
- Gestational Diabetes Mellitus (GDM), Pregnancy Complications, History of Bariatric Surgery
- Keywords
- Gestational Diabetes Mellitus, Bariatric Surgery, Glucose Intolerance, Glycemic Markers, Oral Glucose Tolerance Test
- Medical subject headings
- Diabetes, Gestational, Pregnancy Complications, Glucose Intolerance
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 |
|---|---|---|
| OGTT Tolerant Group | Pregnant women with a history of bariatric surgery who tolerate and complete the 75-gram oral glucose tolerance test during pregnancy. | |
| OGTT Non-Tolerant Group | Pregnant women with a history of bariatric surgery who are unable to tolerate or refuse the 75-gram oral glucose tolerance test during pregnancy. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Development of Gestational Diabetes Mellitus (GDM)
Diagnosis of gestational diabetes mellitus based on standard 75-gram oral glucose tolerance test (OGTT) criteria or clinical diagnostic criteria in women unable to tolerate OGTT.
Measured: Between 24 and 28 weeks of gestation
Secondary outcomes (1)
Polyhydramnios
Polyhydramnios diagnosed by ultrasound during pregnancy as documented in routine antenatal follow-up.
Measured: Between 24 and 40 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 posted8 Apr 2026
- Study start1 Feb 2026
- Primary completionDec 2027 (estimated)
- Study completionDec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Gestational Diabetes Mellitus (GDM)Studies 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
- Prospective
- Enrolment
- 84 participants (estimated)
- Target duration
- 9 Months
Sponsor and investigators
- Lead sponsor
- Burak Deniz Aydoğdu
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Burak Deniz Aydoğdu, Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization
- Investigators
- Burak Deniz AYDOĞDU, MD, Principal investigator, Prof. Dr. Cemil Taşcıoğlu City Hospital, Department of Obstetrics and Gynecology
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07517406
- Sponsor's protocol ID
- 2026-37
- Acronym
- BARI-GDM
- Status last verified
- Apr 2026
- First submitted
- 2 Mar 2026
- Last updated
- 8 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data (IPD) will not be shared due to institutional policies and national data protection regulations. Although this is a prospective study, the informed consent obtained from participants does not include permission for public data sharing. All collected data will be analyzed in de-identified form and handled in accordance with ethical approval and applicable data protection laws.
Study at a glance
From the registry record, last updated by the sponsor on 8 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Predictive Value of Glycemic Markers for Gestational Diabetes Mellitus and Pregnancy Complications in Pregnant Women With Prior Bariatric Surgery Who Cannot Tolerate Oral Glucose Tolerance Testing
- ClinicalTrials.gov ID
- NCT07517406
- Acronym / sponsor ID
- BARI-GDM / 2026-37
- Conditions
- Gestational Diabetes Mellitus (GDM), Pregnancy Complications, History of Bariatric Surgery
- Keywords
- Gestational Diabetes Mellitus, Bariatric Surgery, Glucose Intolerance, Glycemic Markers, Oral Glucose Tolerance Test
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 84 participants (estimated)
- Lead sponsor
- Burak Deniz AydoğduUniversity, hospital or other
- Study start
- 1 Feb 2026 (actual)
- Primary completion
- Dec 2027 (estimated)
- Study completion
- Dec 2027 (estimated)
- First posted
- 8 Apr 2026 (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.
Gestational diabetes mellitus (GDM) is associated with significant maternal and fetal complications. The standard diagnostic test for GDM is the 75-gram oral glucose tolerance test (OGTT). However, pregnant women who have undergone bariatric surgery may not tolerate OGTT due to dumping syndrome and gastrointestinal side effects. This creates diagnostic challenges in this specific population.
The aim of this prospective observational study is to evaluate whether routinely measured glycemic markers, including fasting blood glucose, postprandial blood glucose, HbA1c, and urinary glucose levels, can predict the development of gestational diabetes mellitus and related pregnancy complications in women with prior bariatric surgery.
Pregnant women aged 18-50 years with a history of bariatric surgery will be enrolled and followed throughout pregnancy. The predictive value of glycemic markers for GDM, macrosomia, and polyhydramnios will be analyzed using multivariable logistic regression models.
This study aims to provide alternative diagnostic approaches for GDM screening in pregnant women who are unable to tolerate OGTT and to contribute to improving maternal and perinatal outcomes in this growing patient population.
Detailed description
Gestational diabetes mellitus (GDM) is a common pregnancy complication associated with increased risks of maternal and perinatal morbidity. Early identification and appropriate management are essential to reduce adverse outcomes such as macrosomia, polyhydramnios, and cesarean delivery.
The standard diagnostic approach for GDM is the 75-gram oral glucose tolerance test (OGTT). However, women with prior bariatric surgery frequently experience intolerance to glucose loading due to dumping syndrome, which limits the reliability and feasibility of OGTT in this population. Consequently, alternative diagnostic strategies are required.
This prospective observational cohort study will be conducted at Prof. Dr. Cemil Taşcıoğlu City Hospital between February 2026 and December 2027. Pregnant women aged 18-50 years with a history of bariatric surgery will be enrolled during the first or second trimester. Participants will be categorized according to OGTT tolerance (tolerated vs. not tolerated/refused).
Baseline demographic characteristics including maternal age, gravidity, parity, obstetric history, and educational status will be recorded. Glycemic parameters assessed during routine antenatal follow-up will include fasting plasma glucose, postprandial glucose, HbA1c levels, and urinary glucose measurements. Second and third trimester ultrasound findings will be documented. Pregnancy outcomes including diagnosis of GDM, macrosomia (birth weight >4000 g), and polyhydramnios will be recorded.
The primary objective is to evaluate the predictive value of routine glycemic markers for GDM. Secondary objectives include assessing their association with macrosomia and polyhydramnios.
Statistical analyses will be performed using SPSS version 27. Continuous variables will be summarized as mean ± standard deviation or median (interquartile range) depending on distribution. Comparisons between groups will be performed using the Mann-Whitney U test. Multivariable logistic regression models will be used to determine independent predictors of GDM and other pregnancy complications after adjustment for potential confounders.
This study aims to provide evidence for alternative screening approaches in pregnant women with prior bariatric surgery who are unable to tolerate OGTT and to improve clinical decision-making in this growing patient population.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Target follow-up
- 9 Months
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| OGTT Tolerant Group | – | –Pregnant women with a history of bariatric surgery who tolerate and complete the 75-gram oral glucose tolerance test during pregnancy. |
| OGTT Non-Tolerant Group | – | –Pregnant women with a history of bariatric surgery who are unable to tolerate or refuse the 75-gram oral glucose tolerance test during pregnancy. |
Who may qualify
- Ages
- 18 to 50 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
- Study population
- The study population consists of pregnant women aged 18-50 years with a history of bariatric surgery prior to conception who were followed at the Department of Obstetrics and Gynecology of Prof. Dr. Cemil Taşcıoğlu City Hospital. Eligible participants have documented glycemic parameters during the first and/or second trimester (including fasting plasma glucose, HbA1c, urine glucose and/or oral glucose tolerance test results) and available third trimester and/or delivery records. Only singleton pregnancies with complete clinical data are included.
Key inclusion criteria (10 listed)
- Pregnant women aged 18-50 years
- Singleton pregnancy
- History of bariatric surgery prior to pregnancy
- Followed at Prof. Dr. Cemil Taşcıoğlu City Hospital, Department of Obstetrics and Gynecology
- Availability of glycemic parameters during early pregnancy (≤14 weeks) and/or between 24 and 28 weeks of gestation (fasting plasma glucose, HbA1c, urine glucose, and/or OGTT results if tolerated)
Key exclusion criteria (0 listed)
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
Development of Gestational Diabetes Mellitus (GDM)
Time frame: Between 24 and 28 weeks of gestation
Diagnosis of gestational diabetes mellitus based on standard 75-gram oral glucose tolerance test (OGTT) criteria or clinical diagnostic criteria in women unable to tolerate OGTT.
1 secondary outcome
Polyhydramnios
Time frame: Between 24 and 40 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 8 Apr 2026.
- Individual participant dataSharing planned: No. Individual participant data (IPD) will not be shared due to institutional policies and national data protection regulations. Although this is a prospective study, the informed consent obtained from participants does not include permission for public data sharing. All collected data will be analyzed in de-identified form and handled in accordance with ethical approval and applicable data protection laws.
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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.
Burak Deniz AYDOĞDU, MD principal investigator
Prof. Dr. Cemil Taşcıoğlu City Hospital, Department of Obstetrics and Gynecology
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 Gestational Diabetes Mellitus (GDM) and Pregnancy Complications, run by Burak Deniz Aydoğdu at 1 site in Turkey (Türkiye).
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 10 inclusion and 0 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 8 Apr 2026. 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 Turkey (Türkiye). 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 Burak Deniz AYDOĞDU, MD (90 539-618-22-28, burakd.1992@hotmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Development of Gestational Diabetes Mellitus (GDM) (time frame: Between 24 and 28 weeks of gestation). 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 8 Apr 2026.