Retinal and choroidal microvascular changes during pregnancy detected with OCTA

Objective: To investigate choroidal and retinal blood flow and thickness changes using optical coherence tomography and optical coherence tomography angiography during pregnancy.

Design: Prospective and case-control study between June 2020 and June 2021.

Methods: This prospective study included 41 eyes of 41 pregnant females and 45 eyes of 45 healthy nonpregnant females. Ocular perfusion pressure, retinal thickness, choroidal thickness, foveal avascular zone (FAZ) area, superficial and deep capillary plexuses (SCP and DCP, respectively), vessel density (VD), and choriocapillaris (CC) VD measurements were evaluated with optical coherence tomography and optical coherence tomography angiography.

Results: There was no significant difference in ocular perfusion pressure, retinal thickness, and choroidal thickness during pregnancy. The FAZ area increased as the gestational weeks progressed (p = 0.011). The FAZ area in the first trimester was significantly smaller than that in the control group (p = 0,029). A decrease in the central SCP and DCP VD in the third trimester and an increase in the CC VD during pregnancy were detected (p = 0.01, p < 0.001, and p < 0.001, respectively). We observed an increase in mean VD for both the SCP and DCP in the second trimester (p = 0.02 and p = 0.027, respectively). In the second and third trimesters, the SCP and DCP VD values were found to be significantly higher than in the control group. During the pregnancy, a significant increase in CC VD was detected.

Conclusion: This is the first prospective study in the literature that evaluates the measurements in all trimesters of pregnancy with optical coherence tomography angiography. We observed significant retinal and choroidal microvascular changes between trimesters of pregnancy and when compared with healthy females.