Changes in Optical Coherence Tomography Angiography Precede Clinical Onset of Placental Insufficiency.

Purpose: This prospective cohort study examined the use of optical coherence tomography angiography (OCTA) to detect in vivo retinal and choroidal variations associated with placental insufficiency, manifesting as fetal growth restriction (FGR) and hypertensive disorders of pregnancy (HDP). Methods: Pregnant women were imaged with OCTA from gestational week 16 and every 4 weeks until week 36. Pregnancy outcomes were categorized into three groups: uncomplicated, complicated by late FGR, or complicated by HDP after 32 weeks. OCTA metrics, including retinal perfusion density (PD), vessel length density (VLD), and choriocapillaris flow deficits (CCFDs), were compared between groups. Results: In uncomplicated pregnancies, OCTA metrics remained stable throughout gestation. In contrast, the FGR group exhibited significant overall increases in superficial VLD (P = 0.016), decreases in deep VLD (P = 0.029), and increases in CCFDs (P = 0.002) throughout pregnancy when compared to the uncomplicated group. The HDP group showed significant overall decreases in both PD (P < 0.001) and VLD (P = 0.019) in the deep layer when compared to the uncomplicated group. Furthermore, CCFDs demonstrated strong potential for early prediction of FGR as early as week 16 (area under the curve = 0.73; P = 0.012). Conclusions: Our pilot study highlights the potential of OCTA to identify retinal and choroidal variations as biomarkers for pregnancy complications, particularly increased CCFDs in FGR.