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

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)

Interventions

DEVICE

Continuous Glucose Monitoring (FreeStyle Libre 2)

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.

DEVICE

Self-Monitoring of Blood Glucose (Capillary Glucose Meter)

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.

Sponsors & Collaborators

• Fundación Sociedad Española de Diabetes

  collaborator UNKNOWN

• Hospital Clinic of Barcelona

  lead OTHER

Principal Investigators

• Federico Migliorelli, MD, PhD · Hospital Clinic of Barcelona

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-07-01

Primary Completion

2027-01-31

Completion

2027-05-31

Countries

• Spain

Study Locations