Maternal ExeRcIse Timing to Optimise Postprandial Glucose in Type 1 Diabetes

NCT05843175 | Completed

• 1 other identifier: 11954
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief 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. 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.

Conditions

Pregnancy in Diabetic; Type 1 Diabetes

Outcome Measures

Primary Outcomes (2)

• 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).

  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).

  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

  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

  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

  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

  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

  assessed in the study phase 1 (10 days) - at visit nº 2, 3, 4 (3 days, 4 h/day)

Other Outcomes (23)

• Placenta completeness

  assessed at birth - 20 minutes

• Neonate height

  assessed at birth - 5 minutes

• Neonate ponderal index

  estimated after birth - 3 minutes

Study Arms (2)

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.

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.

Other: Exercise and meal testing (acute stimuli)

Interventions

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

Non-pregnant women with type 1 diabetes; Pregnant women with type 1 diabetes

Eligibility Criteria

• Age: 20 Years - 40 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• 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.

You may not qualify if:

• 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.
• 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.

Sponsors & Collaborators

• University of Graz: lead
• Medical University of Graz: collaborator

Study Sites (1)

University of Graz

Graz, Styria, 8010, Austria

Location

MeSH Terms

Conditions

Pregnancy in Diabetics; Diabetes Mellitus, Type 1

Interventions

Exercise

Condition Hierarchy (Ancestors)

Pregnancy Complications; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Diabetes Mellitus; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Autoimmune Diseases; Immune System Diseases

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Officials

• Pedro Acosta-Manzano, PhD

  University of Graz

  PRINCIPAL INVESTIGATOR

• Mireille van Poppel

  University of Graz

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, CARE PROVIDER
• Purpose: SUPPORTIVE CARE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Randomised, single-centre, controlled crossover in parallel groups (pregnant and non-pregnant women with type 1 diabetes)

Study Record Dates

• First Submitted: March 27, 2023
• First Posted: May 6, 2023
• Study Start: June 22, 2023
• Primary Completion: September 30, 2025
• Study Completion: September 30, 2025
• Last Updated: December 17, 2025

Record last verified: 2025-12

Locations

AU (1)