An interventional study of STRONG Group Prenatal Care and Usual Prenatal Care in Gestational Diabetes Mellitus (GDM), sponsored by Yale University. Not yet recruiting at 1 site in American Samoa. Open to female participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-05.
Sponsored by Yale University · Not applicable, Interventional, and Prevention
Gestational diabetes is a type of diabetes that develops during pregnancy and can increase the risk of health problems for both mothers and babies. Gestational diabetes is particularly common in American Samoa, where there is a need for effective approaches to prevent the condition and help pregnant women manage their blood sugar.
The goal of this clinical trial is to determine whether a group prenatal care program called Strong Together Raising Our Next Generation (STRONG) can reduce the risk of developing gestational diabetes among pregnant women with overweight or obesity in American Samoa. The study will also examine whether additional group-based education and support can improve blood sugar control among women who develop gestational diabetes.
Researchers will enroll 360 pregnant women aged 18 years or older who are in their first 14 weeks of pregnancy. Participants will be randomly assigned (like flipping a coin) to receive either STRONG group prenatal care or usual individual prenatal care. STRONG combines routine prenatal care with group discussions, education about healthy eating and physical activity, goal setting, and peer support.
At 24-28 weeks of pregnancy, all participants will be screened for gestational diabetes. Women who do not develop gestational diabetes will continue with their assigned prenatal care. Women who develop gestational diabetes will be randomly assigned a second time to receive either additional group-based diabetes education or usual one-on-one diabetes counseling, alongside their ongoing prenatal care.
The main questions the study aims to answer are:
Does STRONG group prenatal care reduce the number of women who develop gestational diabetes compared with usual prenatal care?
Among women who develop gestational diabetes, which combination of prenatal care and diabetes education leads to better blood sugar control?
Researchers will also examine pregnancy and birth outcomes, infant health, and blood sugar levels after delivery. Participants will be followed until approximately six weeks after giving birth.
The findings may help identify effective, culturally appropriate ways to prevent and manage gestational diabetes in American Samoa and similar communities.
877 studies on the registry are indexed under Diabetes, Gestational; 203 are open to participants now.
This study's planned enrollment of 360 is above the median of 110 across 564 interventional studies indexed under Diabetes, Gestational.
Browse Diabetes, Gestational studies →Yale University is the lead sponsor of 1,770 studies on the registry; 294 are open to participants now.
Of its 221 completed or terminated interventional studies of FDA-regulated products, 129 (58%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Participants must meet all of the following criteria:
Exclusion Criteria:
Individuals cannot participate if they meet any of the following criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
This arm includes participants assigned to STRONG group prenatal care in Stage 1 who do not develop gestational diabetes mellitus (GDM) at 24-28 weeks of gestation. In Stage 1, participants receive culturally adapted group prenatal care combining routine clinical assessment with facilitated education, goal setting, self-monitoring, and peer support. In Stage 2, participants without GDM continue STRONG prenatal care without additional GDM-specific education or counseling.
Behavioral: STRONG Group Prenatal Care
This arm includes participants assigned to usual prenatal care in Stage 1 who do not develop Gestational Diabetes Mellitus (GDM) at 24-28 weeks of gestation. In Stage 1, participants receive standard individual prenatal care through participating healthcare facilities in American Samoa. In Stage 2, participants without GDM continue usual prenatal care without additional GDM-specific education or counseling.
Behavioral: Usual Prenatal Care
This arm includes participants assigned to STRONG group prenatal care in Stage 1 who develop Gestational Diabetes Mellitus (GDM) at 24-28 weeks and are subsequently randomized to group-based GDM education. In Stage 1, participants receive STRONG group prenatal care. In Stage 2, participants continue their assigned prenatal care and receive additional group-based GDM education emphasizing diabetes self-management, nutrition, physical activity, blood glucose monitoring, and peer support. All clinical GDM treatment remains under the direction of their healthcare providers.
Behavioral: STRONG Group Prenatal Care · Behavioral: Group-Based Gestational Diabetes Education
This arm includes participants assigned to STRONG group prenatal care in Stage 1 who develop Gestational Diabetes Mellitus (GDM) at 24-28 weeks and are subsequently randomized to usual individual GDM counseling. In Stage 1, participants receive STRONG group prenatal care. In Stage 2, participants continue their assigned prenatal care and receive usual one-on-one GDM counseling through local healthcare services, including individualized nutrition and diabetes self-management advice as clinically indicated.
Behavioral: STRONG Group Prenatal Care · Behavioral: Usual Individual Gestational Diabetes Counseling
This arm includes participants assigned to usual prenatal care in Stage 1 who develop Gestational Diabetes Mellitus (GDM) at 24-28 weeks and are subsequently randomized to group-based GDM education. In Stage 1, participants receive standard individual prenatal care through participating healthcare facilities. In Stage 2, participants continue usual prenatal care and receive additional group-based GDM education emphasizing diabetes self-management, nutrition, physical activity, blood glucose monitoring, and peer support. All clinical GDM treatment remains under the direction of their healthcare providers.
Behavioral: Usual Prenatal Care · Behavioral: Group-Based Gestational Diabetes Education
This arm includes participants assigned to usual prenatal care in Stage 1 who develop Gestational Diabetes Mellitus (GDM) at 24-28 weeks and are subsequently randomized to usual individual GDM counseling. In Stage 1, participants receive standard individual prenatal care through participating healthcare facilities. In Stage 2, participants continue usual prenatal care and receive usual one-on-one GDM counseling through local healthcare services, including individualized nutrition and diabetes self-management advice as clinically indicated.
Behavioral: Usual Prenatal Care · Behavioral: Usual Individual Gestational Diabetes Counseling
STRONG is a contextually adapted group prenatal care intervention developed for pregnant women in American Samoa. The program combines routine individual prenatal clinical assessments with facilitated group education, discussion, goal setting, self-monitoring, and peer support. Sessions address healthy gestational weight gain, locally relevant nutrition and physical activity, gestational diabetes prevention and screening, breastfeeding, postpartum weight management, and postpartum diabetes screening. The intervention emphasizes family and peer support and uses culturally relevant examples and educational materials. Group care is delivered alongside routine clinical services by trained facilitators.
Participants receive standard individual prenatal care through participating healthcare facilities in American Samoa. Care is provided by local healthcare professionals according to usual clinical practices and includes routine pregnancy assessments, monitoring of maternal and fetal health, recommended gestational diabetes screening, and referrals or additional clinical management when indicated. Participants do not receive the structured STRONG group prenatal care intervention.
Participants diagnosed with gestational diabetes mellitus (GDM) at 24-28 weeks of pregnancy receive structured, group-based diabetes education in addition to their assigned prenatal care. The intervention focuses on gestational diabetes self-management, including nutrition, physical activity, blood glucose monitoring, interpretation of glucose results, and problem-solving strategies. Facilitated group discussions provide opportunities for peer support and culturally relevant education. Participants continue to receive routine clinical GDM management, including medication when prescribed by their healthcare provider.
Also known as: STRONG+
Participants diagnosed with gestational diabetes mellitus (GDM) at 24-28 weeks of pregnancy receive usual one-on-one gestational diabetes counseling through local healthcare services. Counseling includes individualized advice about nutrition, physical activity, blood glucose monitoring, and diabetes self-management, according to standard clinical practice and available services. Participants continue their assigned prenatal care and receive additional clinical management, including medication when prescribed by their healthcare provider. They do not receive the study's structured group-based GDM education intervention.
Incidence of Gestational Diabetes Mellitus (GDM)
The proportion of participants diagnosed with gestational diabetes mellitus (GDM) based on a 75-g, 2-hour oral glucose tolerance test (OGTT), using International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria applied in American Samoa. GDM is defined as one or more of the following plasma glucose values: fasting ≥92 mg/dL, 1-hour ≥180 mg/dL, or 2-hour ≥153 mg/dL. GDM incidence will be compared between participants initially randomized to STRONG group prenatal care and those randomized to usual prenatal care.
Time frame: 24-28 weeks of gestation
Continuous Glucose Monitoring Time in Range at 30-32 Weeks
Among participants diagnosed with gestational diabetes mellitus (GDM), glycemic control will be assessed using blinded continuous glucose monitoring (CGM). The outcome is the average daily percentage of CGM time spent within the pregnancy target glucose range of 63-140 mg/dL during the 30-32-week monitoring period. Higher percentages indicate better glycemic control. Mean daily time in range will be compared across the four embedded adaptive intervention pathways defined by initial prenatal care assignment and subsequent GDM education assignment.
Time frame: 30-32 weeks of gestation
Continuous Glucose Monitoring Time in Range at 36-38 Weeks
Among participants diagnosed with gestational diabetes mellitus (GDM), glycemic control will be assessed using blinded continuous glucose monitoring (CGM). The outcome is the average daily percentage of CGM time spent within the pregnancy target glucose range of 63-140 mg/dL during the 36-38-week monitoring period. Higher percentages indicate better glycemic control. Mean daily time in range will be compared across the four embedded adaptive intervention pathways defined by initial prenatal care assignment and subsequent GDM education assignment.
Time frame: 36-38 weeks of gestation
Incidence of Preterm Birth
The proportion of participants who give birth before 37 completed weeks of gestation, based on the best obstetric estimate of gestational age documented in the delivery medical record. Preterm birth will be classified as a binary outcome (yes/no). Gestational age at birth will also be recorded in completed weeks.
Time frame: At delivery (before 37 completed weeks of gestation)
Incidence of Cesarean Birth
The proportion of participants who deliver by cesarean section, as documented in the maternal delivery medical record. Cesarean birth will be classified as a binary outcome (yes/no). Mode of delivery will also be recorded as vaginal, assisted vaginal, planned cesarean, or emergency cesarean for descriptive analyses.
Time frame: At delivery
Incidence of Macrosomia (Birthweight Greater Than 4,000 g)
The proportion of infants born with a birthweight greater than 4,000 grams, as documented in the infant's birth medical record. Macrosomia will be classified as a binary outcome (yes/no). Birthweight will also be recorded in grams as a continuous measure.
Time frame: At birth
Incidence of Neonatal Hypoglycemia
The proportion of infants with documented neonatal hypoglycemia during the birth hospitalization. Neonatal hypoglycemia will be defined as a documented blood glucose value below 2.6 mmol/L (approximately 47 mg/dL), a clinical diagnosis of hypoglycemia, or treatment for hypoglycemia. Infants without documented hypoglycemia, including low-risk infants who are not routinely screened, will be classified as having no documented neonatal hypoglycemia.
Time frame: From birth to 6 weeks of age
Incidence of Postpartum Dysglycemia at Approximately 6 Weeks
The proportion of participants with abnormal glucose regulation at approximately six weeks postpartum, assessed using a 75-g, 2-hour oral glucose tolerance test (OGTT). Postpartum dysglycemia will be defined as a fasting plasma glucose of 100 mg/dL or greater and/or a 2-hour plasma glucose of 140 mg/dL or greater. Fasting glucose of 100-125 mg/dL or 2-hour glucose of 140-199 mg/dL indicates prediabetes, while fasting glucose of 126 mg/dL or greater or 2-hour glucose of 200 mg/dL or greater indicates provisional diabetes requiring clinical confirmation.
Time frame: Approximately 6 weeks postpartum
Total Gestational Weight Gain (kg)
Total gestational weight gain will be calculated in kilograms as the difference between the participant's measured weight at enrollment (before 14 weeks of gestation) and the last available prenatal weight.
Time frame: Enrollment (before 14 weeks of gestation) through the last prenatal weight assessment (up to delivery).
Prevalence of Exclusive Breastfeeding at 6 Weeks Postpartum
The proportion of participants who report providing only breast milk to their infant at approximately six weeks postpartum, assessed by maternal questionnaire. Exclusive breastfeeding will be defined as feeding the infant breast milk, either directly from the breast or as expressed breast milk, without supplementation with formula or other foods or liquids.
Time frame: Approximately 6 weeks postpartum.
Intervention Reach Among Screened Pregnant Women
Intervention reach will be assessed using study recruitment and eligibility logs. The measure will be calculated as the percentage of eligible women who enroll and are randomized into the study, among all eligible women identified during recruitment. Recruitment and eligibility counts will also be summarized to characterize the study population and potential reach of the intervention.
Time frame: Throughout the recruitment period (approximately 3 years).
Participant Retention Through Postpartum Follow-up
Participant retention will be measured as the percentage of randomized participants who complete each major scheduled research assessment, including gestational diabetes screening at 24-28 weeks, late-pregnancy assessment at 36-38 weeks, and postpartum assessment at approximately six weeks after delivery. Retention will be calculated using the number of participants randomized as the denominator.
Time frame: Enrollment through approximately 6 weeks postpartum.
Proportion of Expected Prenatal Care Visits Completed
Prenatal care engagement will be assessed as the percentage of expected prenatal care visits completed during pregnancy. For each participant, the number of attended prenatal care visits will be divided by the number of visits expected based on gestational age at enrollment, gestational age at delivery, and the recommended prenatal care schedule. STRONG group prenatal care sessions and usual individual prenatal care appointments will both count as completed prenatal care visits. Higher percentages indicate greater engagement with assigned prenatal care.
Time frame: From randomization (before 14 weeks of gestation) through delivery.
Dose of STRONG Group Prenatal Care Received
Intervention dose will be assessed among participants randomized to STRONG group prenatal care as the number and proportion of scheduled STRONG group sessions attended during pregnancy. The proportion will be calculated by dividing the number of sessions attended by the number of sessions scheduled for each participant. Higher values indicate greater exposure to the structured STRONG intervention.
Time frame: From randomization through delivery.
Fidelity to the STRONG Intervention Protocol
Intervention fidelity will be assessed using a standardized study checklist applied to monthly audio-recorded group intervention sessions. Fidelity will be calculated as the percentage of required intervention elements delivered during assessed sessions. Higher percentages indicate greater fidelity to the intervention protocol.
Time frame: Throughout intervention delivery during pregnancy (up to delivery).
Participant-Reported Acceptability of STRONG Group Prenatal Care
Acceptability of the STRONG group prenatal care intervention will be assessed using a structured participant questionnaire developed for the original STRONG pilot trial. Responses will be summarized to describe participants' experiences, satisfaction, and preferences regarding the group prenatal care model.
Time frame: During pregnancy and through approximately 6 weeks postpartum.
Plan to share: Yes — De-identified individual participant data underlying published study findings will be shared through the NICHD Data and Specimen Hub (DASH), an NIH controlled-access repository. Shared datasets may include questionnaire, clinical, medical record-derived, anthropometric, continuous glucose monitoring, and derived analytic data. Only data from participants who consent to secondary data sharing, and for whom applicable Institutional Review Board (IRB) determinations permit sharing, will be made available. Access will require approval through the NICHD DASH Data Access Committee, execution of a Data Use Agreement, and compliance with study-specific data-use restrictions, including applicable American Samoa IRB requirements. Direct identifiers and participant linkage files will not be shared.
Supporting information: Study protocol, Informed consent form
Time frame: Data underlying peer-reviewed publications will be made available by the time of publication. Data underlying other study findings will be shared by the end of the award period, including any no-cost extensions. Data will remain available for at least as long as required by NICHD DASH repository policies and applicable journal policies.
Access criteria: Qualified researchers may request access to de-identified data through NICHD DASH. Access requires identity verification, approval by the DASH Data Access Committee, and an executed NICHD DASH Data Use Agreement. Researchers must comply with study-specific data-use restrictions and applicable IRB requirements. Additional requirements may include documentation of American Samoa IRB approval or acknowledgement and sharing resulting research findings with the American Samoa IRB and scientific community. Data may not be sold or used for commercial purposes.
Data sharing details ↗ · dash.nichd.nih.gov
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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