Flash Glucose Monitoring Targets in Gestational Diabetes (FlaG-TaG)

The use of glucose monitoring sensors is already well-established in pregnant women with type 1 diabetes (T1D), where it has been proven to improve glycemic control and perinatal outcomes. However, it has not yet been sufficiently researched in the area of gestational diabetes (GDM). Some smaller studies have shown a favorable effect on glycemic control, but no statistically significant differences were observed in reducing perinatal complications. A randomized, prospective study will include 200 pregnant women with GDM, treated at the Diabetes Outpatient Clinic of the Clinical Department of Endocrinology, Diabetes, and Metabolic Diseases at the University Medical Centre Ljubljana. Participants will be divided into two groups. The first group will measure subcutaneous glucose using FSL in addition to self-monitoring of blood glucose (SMBG) while fasting and 60 minutes after main meals at the same time intervals. In both groups, glycemic targets, maternal outcomes, and neonatal outcomes will be monitored. In the FSL + SMBG group, sensor parameters for glycemic control will also be tracked.

Study Overview

• Status: Completed
• Conditions: Gestational Diabetes Mellitus (GDM)
• Intervention / Treatment: Device: Use of FreeStyle Libre 14 day Flash Glucose Monitoring System; Other: No intervention

• Study Type: Interventional
• Enrollment (Actual): 205
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Slovenia
  • Ljubljana, Slovenia, 1000
    • University Medical Centre Ljubljana

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Pregnant women treated at the Diabetes Outpatient Clinic of the Clinical Department of Endocrinology, Diabetes, and Metabolic Diseases for gestational diabetes (GDM),
2. Agreement with the study protocol and ability to follow the study protocol,
3. Diagnosis of GDM established using the standard recommended OGTT method between the 24th and 28th weeks of pregnancy,
4. Age between 18 and 40 years.

Exclusion Criteria:

1. History of bariatric surgery,
2. Treatment with systemic corticosteroids for more than 14 days prior to inclusion in the study,
3. Multiple pregnancy,
4. Hospitalization for psychiatric illness within the last year,
5. First visit to the Diabetes Outpatient Clinic after the 34th week of gestation.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Pregnant women with GDM using FGM and SMBG; Pregnant women with GDM using Flash Glucose Monitoring (FGM) and Self-Monitoring of Blood Glucose (SMBG)	Device: Use of FreeStyle Libre 14 day Flash Glucose Monitoring System; Women with GDM in the intervention arm will use Flash Glucose Monitoring (FGM) from diagnosis until the end of pregnancy
Active Comparator: Pregnant women with GDM using only SMBG	Other: No intervention; Only using SMBG

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glycemic control	Average Fasting Glucose Concentration: Measured in mmol/L, calculated from fasting blood glucose readings and average Postprandial Glucose Concentration: Measured in mmol/L, based on glucose readings taken 60 minutes after main meals.	Up to delivery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Glucose (MG) in FSL+ SMBG group	Measured in millimoles per liter (mmol/L), reflecting the average glucose level recorded by the sensor.	Up to delivery
Mean Amplitude of Glycemic Excursions (MAGE) (FSL+SMBG group)	Measured in millimoles per liter (mmol/L), representing glycemic variability.	Up to delivery
Time in Range - TIR (SMBG+FSL group)	Defined as the percentage (%) of time sensor glucose levels fall between 3,5 and 7,8 mmol/l	Up to delivery
Adherence to the Intervention	Measured as the percentage (%) of completed prescribed self-monitoring and sensor glucose readings relative to the total number of prescribed measurements.	Up to delivery
Gestational Weight Gain (GWG)	Measured in kilograms (kg), calculated as the difference between pre-pregnancy weight and the last recorded weight before delivery.	Up to delivery
Mode of Delivery	Categorized into vaginal delivery, assisted vaginal delivery, or cesarean section, and reported as percentages (%) for each category.	At delivery
Occurrence of Hypertensive Disorders	Reported as a binary outcome (Yes/No), based on clinical diagnosis during pregnancy.	Up to delivery
Birth Weight	Measured in grams (g), recorded immediately after delivery	At birth of infant
Large-for-Gestational-Age (LGA) Infant	Defined as birth weight above the 90th percentile for gestational age, reported as a binary outcome (Yes/No).	At birth of infant
Small-for-Gestational-Age (SGA) Infant	Defined as birth weight below the 10th percentile for gestational age, reported as a binary outcome (Yes/No).	At birth of infant
Gestational Age at Birth	Measured in completed weeks, based on the interval from the first day of the last menstrual period or ultrasound-confirmed dating.	At birth of infant
Neonatal Hypoglycemia	Defined as blood glucose levels below 2.6 mmol/L in the first 48 hours of life, reported as a binary outcome (Yes/No).	At birth of infant
Pregnancy loss	Miscarriage, stillbirth, neonatal death	<28 days of life
Hyperbilirubinemia	Treated with phototherapy	Within first 7 days of life

Collaborators and Investigators

• Sponsor: University Medical Centre Ljubljana

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2022
• Primary Completion (Actual): February 1, 2025
• Study Completion (Actual): February 1, 2025

Study Registration Dates

• First Submitted: December 4, 2024
• First Submitted That Met QC Criteria: January 8, 2025
• First Posted (Actual): January 14, 2025

Study Record Updates

• Last Update Posted (Actual): August 19, 2025
• Last Update Submitted That Met QC Criteria: August 18, 2025
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Keywords: Pregnancy; Gestational diabetes mellitus; Flash Glucose Monitoring; FGM
• Additional Relevant MeSH Terms: Urogenital Diseases; Endocrine System Diseases; Female Urogenital Diseases and Pregnancy Complications; Metabolic Diseases; Pregnancy Complications; Glucose Metabolism Disorders; Diabetes, Gestational; Diabetes Mellitus
• Other Study ID Numbers: 0120-449/2021/15

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes