What Continuous Glucose Monitoring Reveals During Pregnancy With Type 1 Diabetes

High blood sugar during pregnancy affects about half of all pregnant women with type 1 diabetes. These complications can impact both the pregnant person's health and the developing baby. Managing blood sugar carefully throughout pregnancy is therefore a critical part of prenatal care for women with type 1 diabetes.

For decades, the standard approach relied on fingerstick blood tests and insulin pumps or injections. But continuous glucose monitoring (CGM)—small sensors that track blood sugar in real time—offers a different picture of how glucose levels change throughout the day and night.

A major randomized clinical trial published in late 2025 tested closed-loop insulin delivery (a system where CGM data automatically adjusts insulin dosing) against standard care in pregnant women with type 1 diabetes. The study included 88 women across Canada and Australia, followed from early pregnancy through six weeks after delivery.

The results were substantial: women using closed-loop systems spent 65% of their time in the pregnancy-specific target glucose range (63–140 mg/dL), compared to 50% for those on standard care. That 15-percentage-point difference translated to about 3.5 more hours per day in healthy ranges during weeks 16 to 34 of pregnancy.

Severe low blood sugar episodes were rare in both groups, and the closed-loop group had no additional safety concerns compared to standard therapy.

CGM removes guesswork from glucose management. Instead of checking blood sugar a handful of times per day, sensors provide continuous data—showing trends, patterns, and sudden changes in real time. Patients and their care teams can see how food, activity, and stress affect glucose levels and adjust treatment plans accordingly.

For pregnant women with diabetes, this detailed information is especially valuable. Pregnancy itself changes how the body uses insulin, and hormonal shifts can make blood sugar unpredictable. CGM data helps clinicians spot these changes quickly and make timely adjustments to keep both mother and baby safe.

While CGM clearly benefits pregnant women with type 1 diabetes, evidence is more limited for type 2 diabetes and gestational diabetes in pregnancy. Researchers are actively working to fill these gaps.

New studies are also examining automated insulin delivery systems (where CGM data adjusts insulin dosing automatically) to understand their full impact on maternal health, baby health, and emotional well-being during pregnancy. As these technologies evolve and more pregnant women use them, researchers continue gathering real-world evidence to refine best practices.

CGM technology is now FDA-approved and increasingly covered by insurance, making it more accessible to pregnant women with diabetes than ever before. However, using CGM effectively during pregnancy requires guidance—knowing how to interpret the data, spotting common pitfalls, and working closely with your diabetes and obstetric care team.

If you are pregnant or planning pregnancy with type 1 diabetes, ask your healthcare provider about whether CGM or closed-loop systems might fit your care plan. The growing body of research shows these tools can meaningfully improve glucose control and, potentially, pregnancy outcomes.

Origin: YouTube / Juicebox Podcast (Video report). Evidence: Video report, corroborated with 5 indexed studies. Type1Cure is an information and intelligence hub, not a medical advice service. This article summarizes published research and does not provide diagnosis, treatment, or personal medical guidance. Always talk to your own care team before changing anything about your Type 1 diabetes management.