How is the posterior ocular segment affected in cesarean section and normal vaginal delivery?

To evaluate the effects of normal vaginal delivery (NVD) and cesarean section (CS) on the retina, optic disc, and choroid in healthy pregnant women by using optical coherence tomography (OCT).

This prospectively designed study included 60 healthy pregnant women, of whom 30 underwent NVD and 30 underwent CS. Ophthalmological examinations and OCT scans were performed on all pregnant women during the third trimester and the first postpartum week. The measurements were compared between the two visits within each group. Central retinal thickness, ganglion cell layer and inner plexiform layer (GCL + IPL) thickness, peripapillary retinal nerve fiber layer thickness, and optic disc morphology were determined using OCT scans. Central, nasal, and temporal choroidal thicknesses were manually measured using HD-line OCT. Choroidal vascular parameters were calculated from HD-line OCT scans by using a special image processing module. The ratio of the luminal choroidal area to the total choroidal area was determined as the choroidal vascular index (CVI).

In the NVD group, the thinning in the mean and inferior pRNLF, the decrease in the rim area, and the increase in the mean cup/disc and cup volume at the first postpartum week were found to be statistically significant (P < 0.05). In the same group, the CVI was calculated as 0.69 ± 0.02 in the third trimester and 0.66 ± 0.03 in the first postpartum week (P = 0.001). In the CS group, except for the increase in the GCL + IPL thickness, no significant difference was detected in the measurements of the retina, optic disc, and choroid (P < 0.001 and P > 0.05).

This is the first study to evaluate the effect of the delivery method on the retina, choroid, and optic disc. In NVD, changes in the choroidal vascular structure and optic disc morphology can be observed in the early postpartum period, which may be attributed to hormonal effects.