An observational study in Gestational Diabetes Mellitus (GDM) and Lactating Mother, sponsored by Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization. Recruiting at 2 sites in Turkey (Türkiye). Open to female participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-03.
Sponsored by Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization · Observational
Gestational diabetes mellitus (GDM) is a common metabolic disorder of pregnancy associated with increased maternal and fetal morbidity. Lactation has been suggested to improve maternal glucose metabolism, enhance insulin sensitivity, and reduce the risk of future glucose intolerance. However, evidence regarding the protective effect of lactation on the development of GDM in subsequent pregnancies remains limited.
This prospective observational cohort study aims to evaluate the association between lactation and the risk of gestational diabetes mellitus and related pregnancy complications in women who conceive during the lactation period. Routine glycemic markers including fasting plasma glucose, HbA1c, glycosuria, and 75-g oral glucose tolerance test (OGTT) results will be recorded. Ultrasonographic findings including fetal abdominal circumference percentile, estimated fetal weight percentile, and amniotic fluid index will also be assessed. The study will investigate whether lactation is associated with a reduced risk of GDM, fetal macrosomia, and polyhydramnios in subsequent pregnancies.
Gestational diabetes mellitus (GDM) is one of the most common metabolic complications of pregnancy and is associated with adverse maternal and neonatal outcomes, including fetal macrosomia, polyhydramnios, cesarean delivery, and future development of type 2 diabetes mellitus. Early identification of women at increased risk of GDM is essential for optimizing antenatal care and improving pregnancy outcomes.
Lactation has been reported to exert beneficial metabolic effects through increased glucose utilization, improved insulin sensitivity, and facilitation of postpartum weight loss. Previous studies have suggested that breastfeeding may reduce the long-term risk of type 2 diabetes in women with a history of GDM. However, evidence regarding the protective effect of lactation on the occurrence of gestational diabetes mellitus in subsequent pregnancies remains limited.
The present prospective observational cohort study aims to evaluate the relationship between lactation and the development of gestational diabetes mellitus in women who become pregnant during the lactation period. Pregnant women aged 18-50 years with singleton pregnancies who attend the participating obstetrics and gynecology clinics will be enrolled. Routine laboratory parameters obtained during antenatal care, including fasting plasma glucose, HbA1c, glycosuria, and 75-g oral glucose tolerance test (OGTT) results, will be recorded.
In addition, routine ultrasonographic measurements, including fetal abdominal circumference percentile (AC), estimated fetal weight percentile (EFW), and amniotic fluid index (AFI), will be collected during the second and third trimesters. Maternal demographic and obstetric characteristics, including age, gravidity, parity, abortion history, and educational status, will also be documented.
The primary objective of the study is to determine whether lactation is associated with a reduced risk of gestational diabetes mellitus. Secondary objectives include evaluating the association between lactation and pregnancy complications related to altered glucose metabolism, including fetal macrosomia and polyhydramnios. The findings of this study may contribute to a better understanding of the metabolic effects of lactation and provide evidence for strategies aimed at reducing the burden of gestational diabetes mellitus in future pregnancy.
842 studies on the registry are indexed under Diabetes, Gestational; 198 are open to participants now.
This study's planned enrollment of 140 is below the median of 200 across 269 observational studies indexed under Diabetes, Gestational.
Browse Diabetes, Gestational studies →Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization is the lead sponsor of 84 studies on the registry; 18 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Pregnant individuals aged 18-50 years who conceived during the lactation period and are receiving antenatal care at participating obstetrics and gynecology clinics. Participants must have singleton pregnancies and available routine glycemic and ultrasonographic follow-up data. The study population represents women undergoing standard prenatal care in a tertiary care and secondary care hospital setting.
Exclusion Criteria:
Singleton pregnant women aged 18-50 years who conceived during the lactation period and were followed at participating obstetrics and gynecology clinics.
Incidence of Gestational Diabetes Mellitus
Occurrence of gestational diabetes mellitus diagnosed by the 75-g oral glucose tolerance test performed between 24 and 28 weeks of gestation.
Time frame: 24-28 weeks of gestation
Fetal Macrosomia
Presence of fetal macrosomia assessed according to routine obstetric ultrasonographic evaluation and/or birth weight.
Time frame: From second trimester until delivery
Polyhydramnios
Development of polyhydramnios determined by routine ultrasonographic assessment of amniotic fluid volume during pregnancy.
Time frame: From second trimester until delivery
Plan to share: No — Individual participant data (IPD) will not be shared because the study involves patient-level clinical data collected from routine medical records. Data sharing is not included in the current study protocol or ethics committee application, and participant confidentiality and institutional data protection policies will be maintained.
No publications or documents are linked to this record.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization