A growing body of evidence suggests that the metabolic environment of pregnancy leaves a lasting imprint on the eyes of the next generation. Now, researchers from the Nanjing Eye Study report that children born to mothers with gestational diabetes mellitus (GDM) show early, measurable alterations in ocular microvasculature, long before any clinical disease appears.
A closer look at the microvasculature
The team, based at the First Affiliated Hospital with Nanjing Medical University, Nanjing, China, evaluated 681 seven-year-olds from the study, 41 of whom were born to mothers with GDM. Using optical coherence tomography angiography (OCTA), they quantified retinal and choriocapillaris (CC) parameters to compare vascular features between exposed and unexposed offspring.
After adjustment for age, sex, birth weight, body-mass index and ocular biometry, the analysis revealed distinct microvascular differences. Children exposed to maternal GDM exhibited a significantly higher vessel density (VD) in the deep vascular complex (DVC) of the parafoveal temporal quadrant and larger CC flow-void size and area. Superficial capillary plexus density, foveal avascular zone, macular thickness and subfoveal choroidal thickness were not observed to differ between groups.
Clues to early pathophysiology
The findings suggest that maternal hyperglycaemia may subtly compromise choroidal perfusion in utero, with compensatory hyperperfusion in the deeper retinal layers of the child’s macula. This pattern mirrors early changes seen in diabetic adults: reduced CC flow preceding overt retinopathy.
As the study authors note, "the area and size of CC flow voids both increased in offspring exposed to maternal GDM, suggesting that these offspring might have already had reduced CC blood perfusion before they developed diabetes or DR [diabetic retinopathy]." Such microvascular signatures could therefore act as a biomarker of future metabolic or ocular risk, detectable long before systemic abnormalities emerge.
A window into future risk
Previous research has linked GDM to a higher lifetime risk of diabetes, obesity, and refractive errors in exposed offspring. The current OCTA data adds a retinal dimension to that picture. If validated longitudinally, reduced CC perfusion might help identify children who warrant closer monitoring for myopia or later diabetic eye disease.
And while no immediate clinical interventions arise from these findings, they underscore that the effects of gestational diabetes extend beyond systemic metabolism — potentially shaping ocular microcirculation in the developing child. As OCTA technology becomes more accessible, subtle microvascular differences like those revealed here could offer an early warning system for future retinopathy risk. The Nanjing Eye Study thus highlights an emerging frontier: using pediatric retinal imaging to read the echoes of maternal metabolism.
