| Recommended Time-in-Range | β₯70% (3.5β7.8 mmol/L) |
| Fasting Target | 3.5β5.3 mmol/L |
| Post-meal Target (1hr) | Under 7.8 mmol/L |
| Key Devices | Dexcom G6, G7, Libre 3 |
| Sensor Wear Site (2nd/3rd trimester) | Upper arm or thigh |
Key Takeaways
- CGM significantly improves HbA1c and time-in-range during pregnancy
- Targets differ from standard diabetes ranges β tighter control is essential
- Dexcom G6/G7 and Libre 3 are commonly used; consult your care team
- CGM alerts help prevent dangerous nocturnal hypoglycemia
- MDS Diabetes stocks pregnancy-compatible CGM sensors and supplies
Why CGM Matters During Pregnancy
Pregnancy dramatically changes insulin sensitivity, making glucose management far more challenging. For women with Type 1, Type 2, or gestational diabetes, continuous glucose monitoring (CGM) provides real-time data that fingerstick testing simply cannot match. The landmark CONCEPTT trial demonstrated that CGM use in pregnant women with Type 1 diabetes reduced large-for-gestational-age births and NICU admissions significantly.
Pregnancy-Specific Glucose Targets
| Time of Day | Target Range (mmol/L) |
|---|---|
| Fasting / Pre-meal | 3.5 β 5.3 |
| 1 hour post-meal | Under 7.8 |
| 2 hours post-meal | Under 6.4 |
| Overnight | 3.5 β 6.0 |
These targets are considerably tighter than standard diabetes goals. CGM makes achieving them realistic by alerting you to trends before levels go out of range.
Which CGM Devices Are Suitable?
Dexcom G6 & G7
Both are widely used in pregnancy. The G6 has the most clinical trial data in pregnant populations. The G7 offers a slimmer profile and faster warm-up. Neither requires calibration. Wear on the abdomen or upper arm (confirm placement with your midwife as pregnancy progresses).
FreeStyle Libre 3
Provides real-time readings with alarms via the Libre 3 app. More affordable sensor cost. Note: earlier Libre models (1 & 2) are not recommended in pregnancy due to scan-only design β alarms are critical for nocturnal safety.
Sensor Placement Tips During Pregnancy
- Avoid the abdomen from second trimester onward β use upper arm or thigh
- Rotate sites to prevent skin irritation, which worsens with hormonal changes
- Use medical-grade adhesive patches (available at mdsdiabetes.com) to secure sensors as bump grows
- Check sensor accuracy with fingersticks if readings feel wrong, especially near delivery
Managing Alerts and Alarms
Set high alerts at 7.0β7.8 mmol/L and low alerts at 3.8β4.0 mmol/L. Overnight low alerts are particularly important β hypoglycemia is more common in the first trimester and can occur without warning. Share your CGM data with a partner via Dexcom Follow or Libre's sharing feature for added safety.
CGM Data and Your Diabetes Care Team
Upload your CGM reports (Clarity for Dexcom, LibreView for Libre) before every antenatal appointment. Time-in-range, time-below-range, and glucose variability data allow your team to fine-tune insulin doses rapidly. Aim for at least 70% time-in-range (3.5β7.8 mmol/L) as a minimum target.
Recommended MDS Diabetes Products
MDS Diabetes (mdsdiabetes.com) supplies Dexcom G6, G7, and FreeStyle Libre 3 sensors, along with skin-prep wipes, adhesive patches, and overpatch tape specifically suited for pregnancy wear. Fast delivery ensures you never run out of sensors during this critical period.