Assessment of Maternal Retinal Microvasculature in Preterm Pregnancy Using OCT-Angiography: a Cross-Sectional Study

Background: Pregnancy induces a cascade of hemodynamic changes that are likely to affect the maternal systemic and ocular circulation. Objective:The current study aimed to investigate retinal microvasculature alterations in women with preterm and full-term pregnancy using optical coherence tomography angiography (OCT-A). Design:This was a cross-sectional, comparative, single-center study. Methods:The present study included 21 women with preterm pregnancy, who were in the early postpartum period, and 18 controls with full-term pregnancy. Optical coherence tomography angiography imaging was performed to analyze macular microvasculature characteristics at the retinal superficial capillary plexus (SCP) and the choriocapillaris (CC). Results:In females with preterm pregnancy, the mean values of vessel density (VD) at the SCP of the total macular area were significantly higher than those in females with full-term pregnancy (p=0.001), and the mean values of foveal, parafoveal and perifoveal VD at the SCP were higher, though not statistically significant. Similarly, the mean values of perfusion at the SCP of the total macular area were significantly higher in females with preterm pregnancy than controls (p=0.023), while the mean values of foveal, parafoveal and perifoveal perfusion were higher, though not statistically significant. The mean values of foveal avascular zone (FAZ) parameters (area, perimeter, circularity) at the SCP in females with preterm pregnancy did not have any significant differences from those of controls. Concerning the measurements of choroidal parameters, there were no statistically significant differences in subfoveal choroidal thickness, as well as the CC OCT-A characteristics between females with preterm and full-term pregnancy. Conclusions:Our study indicates that retinal blood flow alterations may be present in the early postpartum period in women with preterm pregnancy. Increased macular vasculature may reflect the systemic perfusion changes compensating for placental insufficiency.