Why I Now Push Every Suitable GDM Patient Toward CGM
A pattern I've noticed in my own practice, seeing patients with Gestational Diabetes Mellitus (GDM) at C-MEDiS, has made me a firm believer in continuous glucose monitoring (CGM) as a management tool during pregnancy — not just for Type 1 or Type 2 diabetics, but for GDM specifically.
Among my patients, those who wore a CGM and had their insulin doses titrated based on real-time glucose trends consistently had smoother pregnancies and better outcomes than those managed on conventional fingerstick monitoring alone. Fewer glycemic swings, better time-in-range, and — perhaps most importantly — insulin adjustments that were data-driven rather than reactive to a handful of daily readings.
Why this makes clinical sense
A fingerstick glucose reading is a snapshot. CGM gives the full film — every post-prandial spike, every 3 a.m. dip, every trend a patient would never think to mention at a routine visit. In GDM, where the therapeutic window for glucose control is narrow and the stakes (macrosomia, NICU admission, birth injury) are high, that granularity matters.
This isn't just anecdotal. A secondary analysis of the DiGest trial involving 425 women with GDM found that CGM metrics at 29 weeks were significantly associated with large-for-gestational-age and small-for-gestational-age outcomes, and achieving a pregnancy-specific time-in-range of 90% or higher was linked to a significantly lower risk of LGA babies. A more recent randomized controlled trial comparing real-time CGM plus capillary blood glucose against capillary monitoring alone in GDM pregnancies is currently examining exactly this — time-in-range alongside hypertensive disorders, birth injuries, macrosomia, and NICU admission as outcomes of interest.
A note of honesty
The evidence base isn't uniformly one-sided, and I think it's important to say so. Some earlier trials in pregnant women with diabetes showed no clear benefit of intermittent CGM over standard care on outcomes like large-for-gestational-age rates. What I'm seeing clinically lines up with the more recent, GDM-specific data, but this is still an evolving field, and individual patient factors — how engaged they are with the technology, how promptly dose adjustments are made — matter as much as the device itself.
What this means in practice
For me, this has translated into actively counseling eligible GDM patients on CGM adoption early, rather than waiting for poor control on fingersticks to justify it. Insulin titration becomes a conversation grounded in trends rather than isolated numbers, and patients themselves become more engaged once they can see their own glucose patterns.
If you're managing GDM patients and haven't yet incorporated CGM into your protocol, I'd genuinely be interested in comparing notes — the technology is only going to become more central to how we manage glycemic control in pregnancy.
— Dr. Sai Lakshmikanth Bharathi
Founder & CEO, C-MEDiS, a unit of SB Health, Chennai