Insulin sensitivity patterns across the menstrual cycle in women with type 1 diabetes

Trajectories in Insulin Sensitivity Across Menstrual Cycles in Women With Type 1 Diabetes

This project will use data from your automated insulin delivery system, glucose records, nutrition logs, and menstrual cycle notes to see if insulin needs and glucose patterns change across menstrual cycles in women with type 1 diabetes.

Quick facts

• Study type: Observational
• Enrollment: 350 (estimated)
• Ages: 18 Years to 40 Years
• Sex: Female
• Sponsor: DCB Research AG (other)
• Locations: 1 site (Bern)
• Trial ID: NCT06282055 on ClinicalTrials.gov

What this trial studies

This observational project will collect standardized longitudinal data on insulin dosing, continuous glucose metrics, nutritional intake, and menstrual timing in women with type 1 diabetes who use automated insulin delivery systems. Participants will provide device downloads and cycle logs across multiple consecutive menstrual cycles to capture within-person changes. Researchers will analyze trajectories of insulin sensitivity and glycaemic variability to identify common pattern categories. The aim is to link menstrual cycle phases and characteristics with predictable changes in insulin requirements.

Who should consider this trial

Good fit: Women aged 18 to 40 with type 1 diabetes or LADA for at least one year, regular menstrual cycles, and at least six months of automated insulin delivery system use are ideal candidates.

Not a fit: People who are pregnant or recently postpartum, breastfeeding, using regular systemic hormonal medications, diagnosed with PCOS, have irregular cycles, or are not using an automated insulin delivery system are unlikely to benefit from this study's findings.

Why it matters

Potential benefit: If successful, the findings could help patients and clinicians personalize insulin dosing across the menstrual cycle to reduce episodes of high or low blood glucose.

How similar studies have performed: Previous studies indicate menstrual cycle phases can affect insulin sensitivity and glucose variability, but few have used continuous automated insulin delivery data to define trajectory categories, so this approach is relatively novel.

Eligibility criteria

Inclusion criteria:

* Female sex
* Between 18 and 40 years at inclusion
* Menarche at least one year prior to study inclusion
* Regular menstrual cycle (at least one menstrual cycle in the last 40 days)
* Average menstrual cycle length between 21 and 38 days
* Difference in length between consecutive menstrual cycles of at most 7 days
* Living with type 1 diabetes or latent autoimmune diabetes in adults (LADA) for at least one year
* Actively using an AID system for their diabetes management at least six months prior to study inclusion

Exclusion criteria:

* Regular hormonal intake (e.g. corticosteroids), except: insulin, stable thyroid substitution, and hormonal contraception
* Pregnancy until two months postpartum (ongoing or planned)
* Current breastfeeding (including pumping), as well as two months following complete cessation of breastfeeding and pumping
* Known Polycystic Ovary Syndrome (PCOS)
* Intake of glucocorticoid medication, agents affecting gastric emptying, oral anti-diabetic agents (Metformin) or SGLT-2 inhibitors or GLP-1-analogs
* Individuals with work patterns involving frequent shifts between night and day work (e.g., alternating night and day shifts on a weekly or similar basis).
* Participation in an interventional study within two months preceding and during the present study

Where this trial is running

Bern

• DCB Research AG — Bern, Switzerland (RECRUITING)

Study contacts

• Study coordinator: Stefanie Hossmann, MSc

Conditions: Diabetes Mellitus, Type 1, Menstrual cycle, Trajectories, Women, Insulin sensitivity, Glycaemia, Insulin need