https://doi.org/10.1177/1120672120966566 European Journal of Ophthalmology 1–7 © The Author(s) 2020 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/1120672120966566 journals.sagepub.com/home/ejo EJO European Journal of Ophthalmology Introduction Pregnancy is a physiological state in which a woman’s body undergoes hematologic, vascular, hormonal, and immunologic changes, primarily to provide favorable con- ditions for fetal development. 1 Starting early in pregnancy, women exhibit increased cardiac output and heart rate, as well as vasodilation and reduced systemic vascular resist- ance secondary to hormonal changes, resulting in increased vascular capacity. 2 As occurs in many organs, ocular blood flow is also increased during pregancy. 1 In addition, various ocular changes such as an increase in central corneal thickness and decrease in corneal sensitivity and intraocular pressure have also been reported. 1,3 These adaptations in the eye are speculated to be caused by hormonal, coagulative, and hemodynamic changes during pregnancy. 4 Being the only organ whose vascular tissues can be directly observed, the eye is like a window to the vascular system in terms of understanding the vascular effects of systemic diseases. The choroid has one of the highest blood Evaluation of retinochoroidal tissues in third trimester pregnants: An optical coherence tomography angiography study Abdulmutalip Yildirim 1 , Emin Kurt 1 , Muhammed Altinisik 1 and Yildiz Uyar 2 Abstract Introduction: The structural and vascular changes in the retina and choroid in women in the third trimester of pregnancy were analyzed using optical coherence tomography angiography (OCTA). Methods: Forty women in the third trimester of uncomplicated pregnancy and 40 age-matched healthy women were included. Vascular density (VD) in the superficial and deep capillary plexuses (SCP/DCP), foveal density (FD), and foveal avascular zone (FAZ) area and perimetry measured with OCTA, as well as OCT measurements of central macular thickness (CMT) and choroidal thickness (CT) were compared between the groups. Correlations between structural OCT parameters and vascular OCTA metrics were analyzed. Results: The mean gestational age was 34 (28–41) weeks. Mean age was comparable in the groups (p = 0.732). The pregnant women had significantly higher parafoveal DCP-VD (p = 0.015), FAZ area (p = 0.044), and FD (p = 0.002). Mean subfoveal CT was 21 μm higher in pregnant women but was not significant (p = 0.472). There was no difference in CMT (p = 0.448). FAZ metrics were positively correlated with CT in pregnants and with CMT in the control group (p < 0.05). Parafoveal VD was negatively correlated with CT in the control group (p < 0.05). After adjusting for CT and CMT, the significant difference in VD and FD persisted (p < 0.05), while the difference in FAZ area lost significance (p > 0.05). Conclusions: Considering the effects of the probable covariant factors CMT and CT, systemic changes in pregnant women in their third trimester may cause an increase in VD in the macula and parafoveal DCP. Keywords Retinal pathology/research, retina, techniques of retinal, examination, anatomy/biochemistry/physiology, retinal cell biology Date received: 18 July 2020; accepted: 21 September 2020 1 Ophthalmology Department, Manisa Celal Bayar University, Manisa, Turkey 2 Obstetrics and Gynecology Department, Manisa Celal Bayar University, Manisa, Turkey Corresponding author: Muhammed Altinisik, Ophthalmology Department, Medical School, Manisa Celal Bayar University, Manisa 45040, Turkey. Email: dr.maltinisik@gmail.com 966566EJO 0 0 10.1177/1120672120966566European Journal of OphthalmologyYildirim et al. research-article 2020 Original research article