Retinal and choroidal microvascular features during pregnancy: a systematic review and meta-analysis

To analyse retinal and choroidal microvasculature features in healthy pregnant women using optical coherence tomography angiography (OCTA).

PubMed, Embase, Ovid, Web of Science and Cochrane Library were searched for published studies that compare retinal and choroidal microvasculature characteristics between pregnant females and non-pregnant females from inception to November 2023. The statistics were continuous variables. They were presented as the mean difference (MD) with a corresponding 95% CI. We used Review Manager software 5.4.1 for statistical analysis.

A total of 5 eligible studies involving 219 eyes in the pregnancy group and 186 eyes in the control group were included in the meta-analysis. The pooled results showed that the retinal deep capillary plexus vascular density (DCP VD) measured by OCTA was significantly higher in healthy pregnant women than in controls (MD 1.53; 95% CI 0.62 to 2.44; I²=0%; p=0.0009). However, differences between the two groups in the retinal superficial capillary plexus VD (SCP VD) (MD 0.41;95% CI -1.26 to 2.09; I²=85%; p=0.63), the foveal avascular zone (FAZ) (MD 0.01; 95% CI -0.01 to 0.03; I²=14%; p=0.18), the choriocapillaris VD (CC VD) (MD 0.76; 95% CI -1.11 to 2.64; I²=79%; p=0.43) were uncertain.

Our meta-analysis found that the DCP VD of healthy pregnant women was higher than that of non-pregnant controls. However, differences in SCP VD, FAZ and CC VD between the healthy pregnant women and the non-pregnancy controls were uncertain. Our findings can help to get a deeper understanding of retinal and choroidal microvascular characteristics during pregnancy.