Pregnancy in DiabeticMERIT1DNCT05843175
Maternal ExeRcIse Timing to Optimise Postprandial Glucose in Type 1 Diabetes
A study testing Exercise and meal testing (acute stimuli) in people with Pregnancy in Diabetic and Type 1 Diabetes, run by University of Graz at 1 site in Austria.
Trial summary
Poor glycaemic control in pregnancy is a major factor leading to obstetric complications and future maternal-offspring diseases. This phenomenon is evidenced in women with type 1 diabetes (T1DM), and is worrisome since it is aggravating the disease burden of this and next generations. Read more about this study
- Who is it for?
- Ages 20 to 40 years, women only
- Conditions the study is for
- Pregnancy in Diabetic, Type 1 Diabetes
- What is being tested?
- Exercise and meal testing (acute stimuli)
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20 participants
- Where
- 1 siteAustria
- Study dates
- 22 Jun 2023to 30 Sep 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
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 20 to 40 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- Pregnant women and non-pregnant women with T1DM aged 20-40 years
- Having a BMI of 18-29.9 kg/m2 at pre-pregnancy (pregnant women) or recruitment (non-pregnant)
- Clinical diagnosis of T1DM, or/and multiple daily insulin injections for >1 year, and/or using insulin pump therapy (open-loop).
- Willingness to provide informed consent to participate in the MERIT1D study.
- Being able to read and speak German, English or Spanish well enough to completely understand the instructions, provide informed consent and conduct the experimental procedures.
Who cannot join
- Having poor glycaemic control HbA1c>10% (86 mmol/mol).
- Recurrent severe hypoglycaemia; hospitalisation for diabetic ketoacidosis during the last year.
- Women who smoke or drink alcohol frequently, or require complex diets.
- Having polycystic ovarian syndrome, poorly controlled asthma/allergy, uncontrolled thyroid diseases or hypertension, diabetic ketoacidosis, hepatitis B, hepatitis C, HIV.
- Having severe autoimmune/immunodeficiency, macrovascular, renal, or neuromuscular disease, or severe retinopathy or neuropathy.
- Having any other cardiovascular, pulmonary, orthopaedic, neurologic, psychiatric, or terminal disease, or any other acute/chronic disorder that, in the opinion of the local clinician/researcher, would preclude participation and successful completion of the protocol, or that would directly influence the study results.
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- Use of any medication (e.g., steroids), that, in the opinion of local clinician/researcher, would negatively impact or mitigate full participation and completion, or could influence the study results.
- Any condition that would interfere with compliance or the results, as judged by the Investigator
- Pregnant women: having multiple pregnancy
- Pregnant women: evidence of incompetent cervix, ruptured membranes, placenta previa, foetal malformation, or foetal death.
Trial locations and contacts
1 site in 1 country.
About this study
Poor glycaemic control in pregnancy is a major factor leading to obstetric complications and future maternal-offspring diseases. This phenomenon is evidenced in women with type 1 diabetes (T1DM), and is worrisome since it is aggravating the disease burden of this and next generations.
Exercise is a promising tool to improve glucose control during pregnancy and thus avoid adverse consequences.
The MERIT1D study will explore when is exercise (before or after lunch) more effective to improve postprandial glycaemic control in pregnant and non-pregnant women (of reproductive age) with T1DM, and the mechanisms underlying these metabolic responses.
Read the detailed description
Poor glycaemic control in pregnancy is a major factor leading to obstetric complications and future maternal-offspring diseases (e.g., macrosomia, diabetes). This phenomenon is evidenced in women with type 1 diabetes (T1DM), and is worrisome since it is aggravating the disease burden of this and next generations. Therefore, to find strategies aimed at breaking this intergenerational cycle has become a high-priority. Exercise is a promising tool to improve short-term glycaemic responses such as postprandial glucose peaks and glucose variability, and thus reduce adverse maternal-neonatal outcomes. However, it is unknown which timing of exercise is more effective to optimise postprandial glycaemic control in pregnant women with T1DM, and non-pregnant women (of reproductive age) with T1DM. The mechanisms underlying these benefits in T1DM and pregnancy are also to be established.
The MERIT1D project will unravel which timing of exercise (before or after a meal at lunchtime) is more effective to optimise postprandial glycaemic control in pregnant and non-pregnant women with T1DM, and the mechanisms underlying these metabolic responses. Ten pregnant women with T1DM and ten non-pregnant women with T1DM will be involved in this randomised controlled crossover trial.
Pregnant women at gestational week 16 and 35 (experimental phases 1 and 2, respectively), and non-pregnant peers once after recruitment (experimental phase 1), will undergo 3 experimental conditions within 10 days (random order): pre-meal exercise, post-meal exercise, and non-exercise meal.
Each experimental phase will entail participants attending 4 times to the research centre. Therefore, pregnant women will come to the research centre for a total of 8 study visits, while non-pregnant women will come only to 4 study visits. The acute exercise stimulus will consist of a well-controlled submaximal walking test. The standardised meal provided will consist of a mixed milkshake equivalent to the 35 % of their resting energy expenditure, being made up of approximately 45% carbohydrates, 35% fat, and 20% proteins. Postprandial glycaemic responses will be continuously monitored using last-generation glucose monitoring systems during the 10-day period. Immunometabolic markers (e.g., lipids, cytokines) will be determined in maternal blood and placenta samples.
The MERIT1D study will contribute to the understanding of exercise timing in T1DM and pregnancy, and its underlying mechanisms. This will translate into a better clinical prediction, diagnosis, prognosis and treatment of glycaemic dysregulations, and into more effective exercise programmes for pregnant and non-pregnant women with T1DM.
- Conditions
- Pregnancy in Diabetic, Type 1 Diabetes
- Being tested
- Exercise and meal testing (acute stimuli)
- Medical subject headings
- Pregnancy in Diabetics, Diabetes Mellitus, Type 1
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Exercise and meal testing (acute stimuli)Other
Pre-meal exercise: 1º milkshake intake + 2º exercise test
Post-meal exercise: 1º exercise test + 2º milkshake intake
Non-exercise meal: Only milkshake intake
| Study group | Role | What they receive |
|---|---|---|
| Pregnant women with type 1 diabetes | Experimental | Participants will undergo 3 experimental conditions in random order at week of gestation 16 and 35 (experimental phases 1 and 2): pre-meal exercise, post-meal exercise, and non-exercise meal. Receives: Other: Exercise and meal testing (acute stimuli) |
| Non-pregnant women with type 1 diabetes | Experimental | Participants will undergo 3 experimental conditions in random order after recruitment (experimental phase 1): pre-meal exercise, post-meal exercise, and non-exercise meal. Receives: Other: Exercise and meal testing (acute stimuli) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage of time spent in the euglycemic range for the 24 hours after each experimental condition
- T1DM non-pregnant women, euglycemic range: 3.9 - 10 mmol/L (70 - 180 mg/dL).
- T1DM pregnant women, euglycemic range: 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Percentage of time spent in the euglycemic range for the 24 hours after each experimental condition
- T1DM non-pregnant women: 3.9 - 10 mmol/L (70 - 180 mg/dL).
- T1DM pregnant women: 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Secondary outcomes (30)
Percentage of time spent in hypoglycemia for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: < 3.9 mmol/L (< 70 mg/dL).
- T1DM pregnant women - range: < 3.5 mmol/L (< 63 mg/dL).
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Percentage of time spent in hypoglycemia for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: < 3.9 mmol/L (< 70 mg/dL).
- T1DM pregnant women - range: < 3.5 mmol/L (< 63 mg/dL).
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Percentage of time spent in hyperglycemia for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: > 10 mmol/L (> 180 mg/dL).
- T1DM pregnant women - range: > 7.8 mmol/L (> 140 mg/dL).
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Percentage of time spent in hyperglycemia for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: > 10 mmol/L (> 180 mg/dL).
- T1DM pregnant women - range: > 7.8 mmol/L (> 140 mg/dL).
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Differences in postprandial glucose levels 1-, 2-, and 4-hours post-experiment
Within-change in glucose values (mmol/L) from pre-experiment (before starting exercise/meal testing) to post-experiment (i.e., 1-, 2-, and 4-hours after starting exercise/meal intake) in each experimental day
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 4 h/day)
Differences in postprandial glucose levels 1-, 2-, and 4-hours post-experiment
Within-change in glucose values (mmol/L) from pre-experiment (before starting exercise/meal testing) to post-experiment (i.e., 1-, 2-, and 4-hours after starting exercise/meal intake) in each experimental day
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 4 h/day)
Number of hypoglycaemic events for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: < 3.9 mmol/L (< 70 mg/dL).
- T1DM pregnant women - range: < 3.5 mmol/L (< 63 mg/dL).
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Number of hypoglycaemic events for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: < 3.9 mmol/L (< 70 mg/dL).
- T1DM pregnant women - range: < 3.5 mmol/L (< 63 mg/dL).
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Number of hyperglycaemic events for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: > 10 mmol/L (> 180 mg/dL).
- T1DM pregnant women - range: > 7.8 mmol/L (> 140 mg/dL).
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Number of hyperglycaemic events for the 24 hours after each experimental condition
- T1DM non-pregnant women - range: > 10 mmol/L (> 180 mg/dL).
- T1DM pregnant women - range: > 7.8 mmol/L (> 140 mg/dL).
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Percentage of time spent in nocturnal euglycemia within each experimental day
- T1DM non-pregnant women - range: euglycemia 3.9 - 10 mmol/L (70 - 180 mg/dL).
- T1DM pregnant women - range: euglycaemia 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 00:00 am - 05:59 am)
Percentage of time spent in nocturnal euglycemia within each experimental day
- T1DM non-pregnant women - range: euglycemia 3.9 - 10 mmol/L (70 - 180 mg/dL).
- T1DM pregnant women - range: euglycaemia 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 00:00 am - 05:59 am )
Percentage of time spent in diurnal euglycemia within each experimental day
- T1DM non-pregnant women - range: euglycemia 3.9 - 10 mmol/L (70 - 180 mg/dL).
- T1DM pregnant women - range: euglycaemia 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 6.00 am - 23:59 am)
Percentage of time spent in diurnal euglycemia within each experimental day
- T1DM non-pregnant women - range: euglycemia 3.9 - 10 mmol/L (70 - 180 mg/dL).
- T1DM pregnant women - range: euglycaemia 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 6.00 am - 23:59 am)
Area under the curve of glycaemic exposure
Area under the curve of glycaemic exposure during the 2, 4 and 8 hours after meal intake at each experimental condition.
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 8 hours/day)
Area under the curve of glycaemic exposure
Area under the curve of glycaemic exposure during the 2, 4 and 8 hours after meal intake at each experimental condition.
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 8 h/day)
Glycaemic variability (standard deviation)
Standard deviation (SD) of the mean continuous glucose monitoring levels over the 24 hours after each experimental condition
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Glycaemic variability (standard deviation)
Standard deviation (SD) of the mean continuous glucose monitoring levels over the 24 hours after each experimental condition
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Glycaemic variability (coefficient of variation)
Coefficient of variation of glucose levels over the 24 hours after each experimental condition
Measured: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Glycaemic variability (coefficient of variation)
Coefficient of variation of glucose levels over the 24 hours after each experimental condition
Measured: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Maternal glucose metabolism
Fasting and post-experiment blood samples will be collected using venous puncture in the antecubital vein. Metabolic markers related to the glucose-insulin axis will be analysed (i.e., glucose, insulin, C-peptide and HbA1c).
Measured: assessed in the phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 3 h/day)
Maternal glucose metabolism
Fasting and post-experiment blood samples will be collected using venous puncture in the antecubital vein. Metabolic markers related to the glucose-insulin axis will be analysed (i.e., glucose, insulin, C-peptide and HbA1c).
Measured: assessed in the phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 3 h/day)
Maternal lipid profile
Fasting and post-experiment blood samples will be collected using venous puncture in the antecubital vein. Metabolic markers related to the lipid profile will be analysed (i.e., total cholesterol, high-density lipoprotein (HDL) cholesterol, LDL-cholesterol, triglycerides and free fatty acids).
Measured: assessed in the phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 3 h/day)
Maternal lipid profile
Fasting and post-experiment blood samples will be collected using venous puncture in the antecubital vein. Metabolic markers related to the lipid profile will be analysed (i.e., total cholesterol, high-density lipoprotein (HDL) cholesterol, LDL-cholesterol, triglycerides and free fatty acids).
Measured: assessed in the phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 3 h/day)
Maternal inflammatory markers
Fasting and post-experiment blood samples will be collected using venous puncture in the antecubital vein. Metabolic markers related to inflammatory-immunological responses will be analysed (e.g., IL-6, IL-8, IL-1β, TNFα, C-reactive protein, IFNγ)
Measured: assessed in the phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 3 h/day)
Maternal inflammatory markers
Fasting and post-experiment blood samples will be collected using venous puncture in the antecubital vein. Metabolic markers related to inflammatory-immunological responses will be analysed (e.g., IL-6, IL-8, IL-1β, TNFα, C-reactive protein, IFNγ)
Measured: assessed in the phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 3 h/day)
Placenta weight
Placenta weight (grams)
Measured: assessed at birth - 30 minutes
Placenta biopsies
Eight biopsies will be collected, four on the maternal site and four on the fetal side. Relevant placental proteins (growth factors and cytokines) related to insulin signalling, glucose metabolism, and inflammation will be analysed (e.g., GM-CSF, GCSF, MCP1, TNF-α, IL-6, EGF, IFN-γ, IL-8, IL-10, IL-1β).
Measured: collected at birth - 1 hour
Neonate weight
Neonate weight (grams)
Measured: assessed at birth - 5 minutes
Placenta efficiency
Neonate weight divided by placenta weight
Measured: estimated after birth - 3 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 May 2023
- Study start22 Jun 2023
- Primary completion30 Sep 2025
- Study completion30 Sep 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Pregnancy in DiabeticStudies 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Randomised, single-centre, controlled crossover in parallel groups (pregnant and non-pregnant women with type 1 diabetes)
- Masking
- Double blind
- Who is masked
- Participant, Care provider
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Graz
- Sponsor type
- University, hospital or other
- Collaborators
- Medical University of Graz
- Responsible party
- Sponsor
- Investigators
- Pedro Acosta-Manzano, PhD, Principal investigator, University of GrazMireille van Poppel, Principal investigator, University of Graz
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05843175
- Sponsor's protocol ID
- 11954
- Acronym
- MERIT1D
- Status last verified
- Dec 2025
- First submitted
- 27 Mar 2023
- Last updated
- 17 Dec 2025
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 17 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Maternal ExeRcIse Timing to Optimise Postprandial Glucose in Type 1 Diabetes
- ClinicalTrials.gov ID
- NCT05843175
- Acronym / sponsor ID
- MERIT1D / 11954
- Conditions
- Pregnancy in Diabetic, Type 1 Diabetes
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20 participants (actual)
- Lead sponsor
- University of GrazUniversity, hospital or other
- Collaborators
- Medical University of Graz
- Study start
- 22 Jun 2023 (actual)
- Primary completion
- 30 Sep 2025 (actual)
- Study completion
- 30 Sep 2025 (actual)
- First posted
- 6 May 2023 (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.
Poor glycaemic control in pregnancy is a major factor leading to obstetric complications and future maternal-offspring diseases. This phenomenon is evidenced in women with type 1 diabetes (T1DM), and is worrisome since it is aggravating the disease burden of this and next generations.
Exercise is a promising tool to improve glucose control during pregnancy and thus avoid adverse consequences.
The MERIT1D study will explore when is exercise (before or after lunch) more effective to improve postprandial glycaemic control in pregnant and non-pregnant women (of reproductive age) with T1DM, and the mechanisms underlying these metabolic responses.
Detailed description
Poor glycaemic control in pregnancy is a major factor leading to obstetric complications and future maternal-offspring diseases (e.g., macrosomia, diabetes). This phenomenon is evidenced in women with type 1 diabetes (T1DM), and is worrisome since it is aggravating the disease burden of this and next generations. Therefore, to find strategies aimed at breaking this intergenerational cycle has become a high-priority. Exercise is a promising tool to improve short-term glycaemic responses such as postprandial glucose peaks and glucose variability, and thus reduce adverse maternal-neonatal outcomes. However, it is unknown which timing of exercise is more effective to optimise postprandial glycaemic control in pregnant women with T1DM, and non-pregnant women (of reproductive age) with T1DM. The mechanisms underlying these benefits in T1DM and pregnancy are also to be established.
The MERIT1D project will unravel which timing of exercise (before or after a meal at lunchtime) is more effective to optimise postprandial glycaemic control in pregnant and non-pregnant women with T1DM, and the mechanisms underlying these metabolic responses. Ten pregnant women with T1DM and ten non-pregnant women with T1DM will be involved in this randomised controlled crossover trial.
Pregnant women at gestational week 16 and 35 (experimental phases 1 and 2, respectively), and non-pregnant peers once after recruitment (experimental phase 1), will undergo 3 experimental conditions within 10 days (random order): pre-meal exercise, post-meal exercise, and non-exercise meal.
Each experimental phase will entail participants attending 4 times to the research centre. Therefore, pregnant women will come to the research centre for a total of 8 study visits, while non-pregnant women will come only to 4 study visits. The acute exercise stimulus will consist of a well-controlled submaximal walking test. The standardised meal provided will consist of a mixed milkshake equivalent to the 35 % of their resting energy expenditure, being made up of approximately 45% carbohydrates, 35% fat, and 20% proteins. Postprandial glycaemic responses will be continuously monitored using last-generation glucose monitoring systems during the 10-day period. Immunometabolic markers (e.g., lipids, cytokines) will be determined in maternal blood and placenta samples.
The MERIT1D study will contribute to the understanding of exercise timing in T1DM and pregnancy, and its underlying mechanisms. This will translate into a better clinical prediction, diagnosis, prognosis and treatment of glycaemic dysregulations, and into more effective exercise programmes for pregnant and non-pregnant women with T1DM.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, care provider)
- Number of arms
- 2
- Model description
- Randomised, single-centre, controlled crossover in parallel groups (pregnant and non-pregnant women with type 1 diabetes)
| Arm | Type | Receives |
|---|---|---|
| Pregnant women with type 1 diabetes | Experimental | Other: Exercise and meal testing (acute stimuli)Participants will undergo 3 experimental conditions in random order at week of gestation 16 and 35 (experimental phases 1 and 2): pre-meal exercise, post-meal exercise, and non-exercise meal. |
| Non-pregnant women with type 1 diabetes | Experimental | Other: Exercise and meal testing (acute stimuli)Participants will undergo 3 experimental conditions in random order after recruitment (experimental phase 1): pre-meal exercise, post-meal exercise, and non-exercise meal. |
Who may qualify
- Ages
- 20 to 40 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Pregnant women and non-pregnant women with T1DM aged 20-40 years
- Having a BMI of 18-29.9 kg/m2 at pre-pregnancy (pregnant women) or recruitment (non-pregnant)
- Clinical diagnosis of T1DM, or/and multiple daily insulin injections for >1 year, and/or using insulin pump therapy (open-loop).
- Willingness to provide informed consent to participate in the MERIT1D study.
- Being able to read and speak German, English or Spanish well enough to completely understand the instructions, provide informed consent and conduct the experimental procedures.
Key exclusion criteria (10 listed)
- Having poor glycaemic control HbA1c>10% (86 mmol/mol).
- Recurrent severe hypoglycaemia; hospitalisation for diabetic ketoacidosis during the last year.
- Women who smoke or drink alcohol frequently, or require complex diets.
- Having polycystic ovarian syndrome, poorly controlled asthma/allergy, uncontrolled thyroid diseases or hypertension, diabetic ketoacidosis, hepatitis B, hepatitis C, HIV.
- Having severe autoimmune/immunodeficiency, macrovascular, renal, or neuromuscular disease, or severe retinopathy or neuropathy.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Exercise and meal testing (acute stimuli)Pre-meal exercise: 1º milkshake intake + 2º exercise test Post-meal exercise: 1º exercise test + 2º milkshake intake Non-exercise meal: Only milkshake intake | Other | Non-pregnant women with type 1 diabetes, Pregnant women with type 1 diabetes |
Primary outcome
Percentage of time spent in the euglycemic range for the 24 hours after each experimental condition
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
* T1DM non-pregnant women, euglycemic range: 3.9 - 10 mmol/L (70 - 180 mg/dL). * T1DM pregnant women, euglycemic range: 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
Percentage of time spent in the euglycemic range for the 24 hours after each experimental condition
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
* T1DM non-pregnant women: 3.9 - 10 mmol/L (70 - 180 mg/dL). * T1DM pregnant women: 3.5 - 7.8 mmol/L (63 - 140 mg/dL).
30 secondary outcomes
Percentage of time spent in hypoglycemia for the 24 hours after each experimental condition
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Percentage of time spent in hypoglycemia for the 24 hours after each experimental condition
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Percentage of time spent in hyperglycemia for the 24 hours after each experimental condition
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Percentage of time spent in hyperglycemia for the 24 hours after each experimental condition
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Differences in postprandial glucose levels 1-, 2-, and 4-hours post-experiment
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 4 h/day)
Differences in postprandial glucose levels 1-, 2-, and 4-hours post-experiment
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 4 h/day)
Number of hypoglycaemic events for the 24 hours after each experimental condition
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Number of hypoglycaemic events for the 24 hours after each experimental condition
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Number of hyperglycaemic events for the 24 hours after each experimental condition
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Number of hyperglycaemic events for the 24 hours after each experimental condition
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Percentage of time spent in nocturnal euglycemia within each experimental day
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 00:00 am - 05:59 am)
Percentage of time spent in nocturnal euglycemia within each experimental day
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 00:00 am - 05:59 am )
Percentage of time spent in diurnal euglycemia within each experimental day
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 6.00 am - 23:59 am)
Percentage of time spent in diurnal euglycemia within each experimental day
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 6.00 am - 23:59 am)
Area under the curve of glycaemic exposure
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 8 hours/day)
Area under the curve of glycaemic exposure
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 8 h/day)
Glycaemic variability (standard deviation)
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Glycaemic variability (standard deviation)
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Glycaemic variability (coefficient of variation)
Time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)
Glycaemic variability (coefficient of variation)
Time frame: assessed in the study phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 24 h/day)
Maternal glucose metabolism
Time frame: assessed in the phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 3 h/day)
Maternal glucose metabolism
Time frame: assessed in the phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 3 h/day)
Maternal lipid profile
Time frame: assessed in the phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 3 h/day)
Maternal lipid profile
Time frame: assessed in the phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 3 h/day)
Maternal inflammatory markers
Time frame: assessed in the phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 3 h/day)
Maternal inflammatory markers
Time frame: assessed in the phase 2 (only pregnant women, 10 days) - at visit nº 6, 7, 8 (3 days, 3 h/day)
Placenta weight
Time frame: assessed at birth - 30 minutes
Placenta biopsies
Time frame: collected at birth - 1 hour
Neonate weight
Time frame: assessed at birth - 5 minutes
Placenta efficiency
Time frame: estimated after birth - 3 minutes
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Dec 2025.
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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. This study is not recruiting at the moment.
Pedro Acosta-Manzano, PhD principal investigator
University of Graz
Mireille van Poppel principal investigator
University of Graz
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Exercise and meal testing (acute stimuli) in people with Pregnancy in Diabetic and Type 1 Diabetes, run by University of Graz at 1 site in Austria.
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 5 inclusion and 10 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: finished, as of the sponsor's last update on 17 Dec 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 Austria. 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage of time spent in the euglycemic range for the 24 hours after each experimental condition (time frame: assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 24 hours/day)). The study lists 2 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 17 Dec 2025.