Trial Review

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Trial registered on ANZCTR


Registration number
Help: Registration number
ACTRN12626001009303
Ethics application status
Help: Ethics application status
Approved
Date submitted
Help: Date submitted
7/07/2026
Date registered
Help: Date registered
17/08/2026
Date last updated
Help: Date last updated
17/08/2026
Date data sharing statement initially provided
Help: Data sharing statement date
17/08/2026
Type of registration
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Prospectively registered

Titles & IDs
Public title
Survey for women who have had gestational diabetes.
Scientific title
Postpartum screening and cardiometabolic outcomes in women diagnosed with gestational diabetes mellitus in Auckland, New Zealand
Additional trial identifiers [1] 317820 0
Nil
Universal Trial Number (UTN)
Trial acronym
Related trial records

Health condition
Health condition(s) studied:
Gestational Diabetes 342747 0
Condition category
Condition code
Metabolic and Endocrine 338878 338878 0 0
Diabetes
Cardiovascular 338879 338879 0 0
Other cardiovascular diseases
Renal and Urogenital 339260 339260 0 0
Kidney disease

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of the intervention or exposure
Condition: Gestational Diabetes.
Observation 1: Up to 7 years of primary and secondary healthcare data.
The first data collection point involves retrospective data collection for women who delivered a baby and were enrolled in the Public Health Organisation (PHO), between 2020 and 2024. This means that up to 5 years of data will already be available for some women, and a few months for others. Data collected includes primary care records for diabetes diagnoses and dates, appointment dates, demographic details (ethnicity, decile, age) and blood and urine test results as well as blood pressure measurements. Secondary care data collected is from the national maternity dataset, which holds information about deliveries and demographic details (including age, ethnicity, mode of delivery, birth outcome, pre-eclampsia, diabetes, ventilation and hospitalisation, lead maternity care enrollment, parity, gravida). Data for the infants of these deliveries is also collected (including gestation, prematurity, apgar scores, admissions). This data is all de-identified and unable to be traced to the individual patients. Data will be pooled for analysis.

After the survey, further data from the national datasets will be requested - this will be from Pharms for prescription and dispensing information, National Minimum Dataset (NMDS) for hospital admissions, Labs for blood test results. This data will then include approximately two further years worth of information for all participants.

Observation 2: Quantitative data from questionnaire and interview for randomly selected participants. Participants with GDM from the main cohort (those in observation 1), are randomly selected. Their encrypted ID is then re-identified by the appropriate agency, and their practice will contact them to invite them to the survey. If the participant chooses to make contact with the research team, they will complete informed consent, provide contact details and then fill out an online questionnaire which takes 5-10 minutes and involves questions about ethnicity, education (using standard census format for questions), previous births.

The interviews will be conducted by trained members of the research team and are structured interviews with predefined questions. Data collection is via a study-specific form, which provides check boxes and drop down lists for specific answers and the opportunity to provide more information in free-text fields, to be categorised during analysis. Interviews will be via telephone, take around 10-15 minutes and will not be recorded.
Intervention code [1] 334662 0
Not applicable
Description of the comparator or control
Women without gestational diabetes - for clinical data only.

All women who delivered a baby and were enrolled in the PHO, between 2020 and 2024, and did not have gestational diabetes during this time. Data is collected from primary care records and from national datasets, and is the same as for the exposure group.
Control group
Active

Outcomes
Primary outcome [1] 346088 0
The proportion of women being screened for Type 2 Diabetes (T2DM) (Oral Glucose Tolerance Test (OGTT), HbA1c, serum glucose) at time points within 6 months and 12 months postpartum and annually as recommended.
Timepoint [1] 346088 0
Primary and secondary care data for screening tests at 6 months, 12 months and annually up to 5 years post delivery.
Primary outcome [2] 346241 0
Proportion of women being screened for Cardiovascular (CV) markers (blood pressure, lipids and smoking status) and markers of renal disease, at or within 12 months postpartum and annually. This will be assessed as a composite outcome.
Timepoint [2] 346241 0
Primary and secondary care data for screening tests at 6 months, 12 months and anually up to 5 years post delivery.
Primary outcome [3] 346242 0
Reported factors associated with completion of post-partum screening for diabetes, cardiovascular and renal risk factors, in women with gestational diabetes mellitus (GDM). This will be assessed as a composite outcome.
Timepoint [3] 346242 0
Single time point, between 1 and 5 years post-delivery.
Secondary outcome [1] 465154 0
Demographic factors associated with completion of post-partum screening for diabetes, in women with gestational diabetes mellitus (GDM).
Timepoint [1] 465154 0
Primary and secondary care data for screening tests at 6 months, 12 months and annually up to 5 years post delivery.
Secondary outcome [2] 465155 0
The development of T2DM, up to 7 years post-partum.
Timepoint [2] 465155 0
Primary and secondary care data for health outcomes at 6 months, 12 months and annually up to 7 years post delivery.
Secondary outcome [3] 465156 0
Risk factors and screening status associated with adverse health outcomes. This will be assessed as a composite outcome.
Timepoint [3] 465156 0
Primary and secondary care data for health outcomes at 6 months, 12 months and annually up to 7 years post delivery.
Secondary outcome [4] 466117 0
Demographic factors associated with completion of post-partum screening for cardiovascular risk factors, in women with gestational diabetes mellitus (GDM).
Timepoint [4] 466117 0
Primary and secondary care data for screening tests at 6 months, 12 months and annually up to 5 years post delivery.
Secondary outcome [5] 466118 0
Demographic factors associated with completion of post-partum screening for renal risk factors, in women with gestational diabetes mellitus (GDM).
Timepoint [5] 466118 0
Primary and secondary care data for screening tests at 6 months, 12 months and annually up to 5 years post delivery.
Secondary outcome [6] 466119 0
The development of risk factors for CV (hypertension, dyslipidaemia and smoking), up to 7 years post-partum.
Timepoint [6] 466119 0
Primary and secondary care data for health outcomes at 6 months, 12 months and annually up to 7 years post delivery.
Secondary outcome [7] 466120 0
The development of risk factors for renal disease, up to 7 years post-partum.
Timepoint [7] 466120 0
Primary and secondary care data for health outcomes at 6 months, 12 months and annually up to 7 years post delivery.

Eligibility
Key inclusion criteria
Women who have delivered a baby between 2020 and 2024 from a pregnancy with gestational diabetes, and are enrolled with the Primary Healthcare Organisation at the time of data extraction.
Control cohort will be women who have delivered a baby between 2020 and 2024 from a pregnancy without gestational diabetes and are enrolled with the Primary Healthcare Organisation at the time of data extraction.
Minimum age
16 Years
Maximum age
No limit
Sex
Females
Healthy volunteers
No
Key exclusion criteria
Women with pre-existing Type 1 or Type 2 diabetes diagnosis which occurred before their index pregnancy during the study period.

Study design
Purpose
Screening
Duration
Longitudinal
Selection
Defined population
Timing
Both
Statistical methods / analysis
The sample size was based on pragmatic considerations. As this is an observational survey with no intervention, the primary objective was to ensure adequate representation of priority subgroups (Maori and Pacific women) and to achieve sufficient precision to calculate proportions and explore associations between demographic characteristics and screening and health outcomes. A total sample of 250 was selected as the maximum feasible size given the study resources and the underlying population frame. Of the 250 women, space will be held for 80 Maori women and 80 Pacific women which requires oversampling of these groups.

Frequencies will be generated for categorical variables and T-tests to calculate mean and SD for continuous variables. Comparisons will be made between case and control women for cardiometabolic outcomes (dependent variables) and screening, assessments and management of risk factors. Multivariate regression models will examine associations between independent variables and all outcomes (dependent variables) to generate odd ratios and 95% Confidence Intervals (CI). Cox proportional hazard ratios (HR) and 95% CI and/or Kaplan-Meier will be calculated for prediabetes, T2DM and major CV risk factors (hypertension, dyslipidaemia) and renal markers.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
24/08/2026
Actual
Date of last participant enrolment
Anticipated
23/08/2027
Actual
Date of last data collection
Anticipated
30/06/2028
Actual
Sample size
Target
250
Accrual to date
Final
Recruitment outside Australia
Country [1] 28297 0
New Zealand
State/province [1] 28297 0

Funding & Sponsors
Funding source category [1] 322362 0
Charities/Societies/Foundations
Name [1] 322362 0
New Zealand Society for the Study of Diabetes
Country [1] 322362 0
New Zealand
Primary sponsor type
University
Name
University of Auckland
Address
Country
New Zealand
Secondary sponsor category [1] 325285 0
None
Name [1] 325285 0
Address [1] 325285 0
Country [1] 325285 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 320865 0
Southern Health and Disability Ethics Committee
Ethics committee address [1] 320865 0
Ethics committee country [1] 320865 0
New Zealand
Date submitted for ethics approval [1] 320865 0
11/12/2024
Approval date [1] 320865 0
25/02/2025
Ethics approval number [1] 320865 0
20916

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 151882 0
Dr Barbara Daly
Address 151882 0
Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023
Country 151882 0
New Zealand
Phone 151882 0
+64 9 373 7599 89882
Fax 151882 0
Email 151882 0
[email protected]
Contact person for public queries
Name 151883 0
Jessica Brosnahan
Address 151883 0
Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023
Country 151883 0
New Zealand
Phone 151883 0
+64 9 373 7599
Fax 151883 0
Email 151883 0
[email protected]
Contact person for scientific queries
Name 151884 0
Jessica Brosnahan
Address 151884 0
Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023
Country 151884 0
New Zealand
Phone 151884 0
+64 9 373 7599
Fax 151884 0
Email 151884 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.