Measurement of choroid thickness in pregnant women using enhanced depth imaging optical coherence tomography.

PURPOSE To investigate choroidal thickness in healthy pregnant women during different trimesters using enhanced depth imaging optical coherence tomography (EDI-OCT). METHODS This prospective study included 90 healthy pregnant women in their first, second, or third trimester (groups 1, 2, and 3, respectively) and 30 non-pregnant healthy women (group 4). The age range for all groups was 18-40 years. Spectral domain optical coherence tomography scans were obtained to estimate the average choroidal thickness. Using EDI-OCT, we measured choroidal thickness manually from the outer border of the retinal pigment epithelium to the inner scleral border at the subfovea, 3 mm temporal, and 3 mm nasal to the fovea. Differences among groups were analyzed by one-way ANOVA. RESULTS We found a statistically significant difference between groups 2 and group 4 for subfoveal, temporal, and nasal mean choroidal thickness (p=0.007, p<0.001, p=0.026, respectively). The mean choroidal thickness for group 2 was 395 ± 80 μm, 338 ± 74 μm, and 233 ± 61 μm at the regions subfoveal, temporal, and nasal to the fovea, respectively. In comparison, the mean choroidal thickness for group 4 was 335 ± 86 μm, 274 ± 54 μm, and 200 ± 53 μm at the regions subfoveal, temporal, and nasal to the fovea, respectively. No statistically significant differences were found for choroidal thickness among groups 1-4 (p=0.214, p=0.177, p=0.094, respectively) and between groups 3-4 (p=0.105, p=0.261, p=0.695, respectively) for all measured points. CONCLUSION Our results suggest that choroidal thickening can occur at the regions subfoveal, temporal, and nasal to the fovea in the second trimester.