Subfoveal choroidal thickness in pregnancy: A systematic review with meta-analyses

Pregnancy induces a variety of changes in the eye. Mapping these changes provides a pathophysiological basis for understanding pregnancy-associated ocular disorders. In this systematic review and meta-analysis, our aim was to determine how pregnancy affects subfoveal choroidal thickness and to explore temporal changes in subfoveal choroidal thickness during pregnancy and postpartum. On April 7, 2024, we searched eight literature databases for studies which used macular optical coherence tomography to evaluate subfoveal choroidal thickness in healthy pregnant women. We identified 26 studies summarizing data from 1935 healthy women, of which 1096 were pregnant and 839 non-pregnant. We found that pregnant women had a subfoveal choroidal thickness which was 31.1 μm (95% CI: 19.4-42.7 μm) thicker than non-pregnant women. No statistically significant changes were observed throughout trimesters. From the 3rd trimester to postpartum, we found a reduction in the subfoveal choroidal thickness at -41.9 μm (95% CI: -68.5 to -15.2 μm). In conclusion, in healthy women without ocular disease, pregnancy is associated with a thicker subfoveal choroid indicating a higher choroidal perfusion. Choroidal thickness remains stable across trimesters and is reduced postpartum, indicating a temporary physiological adaptation during pregnancy.