Continuous Glucose Monitoring Versus Self-Monitoring of Blood Glucose in Women With Gestational Diabetes

NCT07558291 | Not Yet Recruiting DMC

• 1 other identifier: HCB/2025/1154
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Gestational diabetes mellitus (GDM) is a type of diabetes that is first diagnosed during pregnancy. It causes high blood sugar levels and can increase the risk of health problems for both the mother and the baby. Babies may grow larger than expected (macrosomia), which can make delivery more difficult and increase the risk of birth complications. Mothers with GDM are also more likely to need insulin treatment and may have a higher risk of high blood pressure during pregnancy. Good blood sugar control is important to reduce these risks. The usual way to monitor blood sugar in women with GDM is by self-monitoring of blood glucose (SMBG). This involves pricking the finger several times a day to measure blood sugar levels. Although this method provides useful information, it only shows glucose levels at specific moments and may miss changes that happen during the night or between measurements. Continuous glucose monitoring (CGM) is a newer method that uses a small sensor placed under the skin to measure glucose levels throughout the day and night. It provides more detailed information about blood sugar patterns and does not require frequent finger pricks. CGM has been shown to improve blood sugar control in people with type 1 and type 2 diabetes, but its benefits in women with gestational diabetes are not yet fully known. The purpose of this study is to compare continuous glucose monitoring (CGM) with standard finger-prick monitoring (SMBG) in pregnant women diagnosed with gestational diabetes between 24 and 28 weeks of pregnancy. The study will evaluate whether CGM is practical to use, whether women are satisfied with it, and whether it may help improve blood sugar control and pregnancy outcomes. A total of 100 pregnant women with gestational diabetes will take part in this study. Participants will be randomly assigned (like flipping a coin) to one of two groups: One group will use a continuous glucose monitoring device. The other group will continue with standard finger-prick blood glucose monitoring. Both groups will receive the same medical care, including dietary advice, physical activity recommendations, and insulin treatment if needed. Participants will attend regular pregnancy visits every 2 to 3 weeks until delivery, as part of usual care. No extra hospital visits are required because of the study. Women using CGM will receive training on how to use the device. The researchers will compare blood sugar control, the need for insulin, pregnancy complications, and newborn outcomes such as birth weight and episodes of low blood sugar after birth. The study will also assess how satisfied women are with their glucose monitoring method and how it affects their quality of life. This is a pilot study, which means its main goal is to determine whether a larger study should be carried out in the future. The results will help researchers understand whether continuous glucose monitoring could improve the care of women with gestational diabetes and their babies.

Conditions

Gestational Diabetes Mellitus (GDM)

Keywords

Gestational Diabetes Mellitus; Continuous Glucose Monitoring; Glycemic Control; Patient-Reported Outcomes; Self-Monitoring of Blood Glucose

Outcome Measures

Primary Outcomes (4)

• Feasibility of Continuous Glucose Monitoring Compared With Standard Self-Monitoring - Recruitment rate

  Number of enrolled participants over number of eligible participants

  From randomization (24-28 weeks of gestation) until delivery

• Feasibility of Continuous Glucose Monitoring Compared With Standard Self-Monitoring - Retention rate

  Number of participants completing the study over number of randomized participants

  From randomization (24-28 weeks of gestation) until delivery

• Feasibility of Continuous Glucose Monitoring Compared With Standard Self-Monitoring - Adherence to assigned monitoring strategy

  Proportion of expected glucose readings completed; ≥80% considered high adherence

  From randomization (24-28 weeks of gestation) until delivery

• Feasibility of Continuous Glucose Monitoring Compared With Standard Self-Monitoring - Data completeness

  Percentage of missing key variables

  From randomization (24-28 weeks of gestation) until delivery

Secondary Outcomes (27)

• Neonatal Outcomes - Birth weight

  At delivery

• Neonatal Outcomes - Large for gestational age

  At delivery

• Neonatal Outcomes - Neonatal hypoglycemia

  From delivery up to hospital discharge

• Neonatal Outcomes - Admission to neonatal intensive care unit

  From delivery up to hospital discharge

• Neonatal Outcomes - Obstetric trauma

  From delivery up to hospital discharge

Study Arms (2)

Continuous Glucose Monitoring (CGM)

EXPERIMENTAL

Participants randomized to this arm will use a real-time continuous glucose monitoring system (FreeStyle Libre 2) from randomization (24-28 weeks of gestation) until delivery. The sensor will be placed by trained staff, and participants will receive standardized training on device use and interpretation of glucose trends. Clinical decisions, including dietary adjustments and initiation or titration of insulin therapy, will be based on CGM data according to local gestational diabetes protocols. A capillary glucose meter will be provided for confirmatory measurements if needed. All other aspects of care will follow standard practice.

Device: Continuous Glucose Monitoring (FreeStyle Libre 2)

Self-Monitoring of Blood Glucose (SMBG)

ACTIVE COMPARATOR

Participants randomized to this arm will perform standard self-monitoring of blood glucose using capillary finger-prick measurements (typically fasting and postprandial values, 4-6 times daily) from randomization until delivery. Participants will receive standardized education on measurement technique and recording. Clinical decisions, including dietary adjustments and insulin initiation or titration, will be based on SMBG values according to local gestational diabetes protocols. All other aspects of care, including obstetric follow-up, will follow standard clinical practice.

Device: Self-Monitoring of Blood Glucose (Capillary Glucose Meter)

Interventions

Continuous Glucose Monitoring (FreeStyle Libre 2) DEVICE

Use of a CE-marked continuous glucose monitoring system (FreeStyle Libre 2) from randomization (24-28 weeks of gestation) until delivery. The sensor measures interstitial glucose continuously and provides real-time glucose values and trend information. Data are reviewed during routine visits or remotely and used to guide clinical management of gestational diabetes, including lifestyle adjustments and insulin initiation or titration when required. A capillary glucose meter may be used to confirm discordant readings.

Continuous Glucose Monitoring (CGM)

Self-Monitoring of Blood Glucose (Capillary Glucose Meter) DEVICE

Standard capillary self-monitoring of blood glucose using a CE-marked glucose meter from randomization until delivery. Participants perform fasting and postprandial finger-prick measurements (typically 4-6 times daily). Glucose values are reviewed during routine visits or remotely and used to guide clinical management of gestational diabetes, including dietary adjustments and insulin initiation or titration according to local protocols.

Self-Monitoring of Blood Glucose (SMBG)

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Pregnant women aged ≥18 years
• Singleton pregnancy
• Diagnosis of gestational diabetes mellitus (GDM) according to local two-step protocol (abnormal 50 g glucose challenge test followed by abnormal 100 g oral glucose tolerance test with at least 2 abnormal values)
• Gestational age between 24 and 28 weeks at time of GDM diagnosis
• Access to a compatible smartphone or digital device with internet connection to allow synchronization and remote upload of glucose data (CGM or SMBG)
• Ability and willingness to provide written informed consent

You may not qualify if:

• Preexisting type 1 or type 2 diabetes mellitus
• History of bariatric surgery
• Treatment with metformin during pregnancy
• Chronic systemic corticosteroid therapy
• Known contraindications to use of a CGM sensor (e.g., severe dermatologic conditions at insertion site)
• Inability to comply with study procedures or follow-up

Sponsors & Collaborators

• Hospital Clinic of Barcelona: lead
• Fundación Sociedad Española de Diabetes: collaborator

Study Sites (1)

Hospital Clínic de Barcelona

Barcelona, Barcelona, 08028, Spain

Location

MeSH Terms

Conditions

Diabetes, Gestational

Interventions

Continuous Glucose Monitoring; Blood Glucose Self-Monitoring

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

Intervention Hierarchy (Ancestors)

Blood Chemical Analysis; Clinical Chemistry Tests; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Diagnostic Techniques, Endocrine; Monitoring, Physiologic; Investigative Techniques; Self-Testing; Self Care; Therapeutics

Study Officials

• Federico Migliorelli, MD, PhD

  Hospital Clinic of Barcelona

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 23, 2026
• First Posted: April 30, 2026
• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): January 31, 2027
• Study Completion (Estimated): May 31, 2027
• Last Updated: April 30, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

ES (1)