The effect of delivery type (vaginal delivery versus cesarean section) on intraocular pressure and retinal nerve fiber layer thickness in healthy women

Introduction: Pregnancy imposes physiological stress and significantly changes human body. This change may have potential effects on visual system. Little is known about pregnancy effects on intraocular pressure (IOP) and glaucoma. Objectives: The present study tended to evaluate and compare the effect of normal vaginal delivery (NVD) versus cesarean section (CS) on IOP and retinal nerve fiber layer thickness (RNFLT) in healthy women. Patients and Methods: Sixty pregnant women participated in this prospective cross-sectional study. The participants were assigned to two groups; the first group consisted of 30 candidates for NVD and the second group of 30 candidates for CS. Then, IOP in three states before delivery, during delivery, and six weeks after delivery then RNFLT were measured and compared by optical coherence tomography (OCT) in two states before delivery and six weeks after delivery. Results: Based on the results, there was no significant difference in the RNFLT in left and right eyes, before and after delivery in the NVD and CS groups (P=0.081 and P=0.090, respectively). Additionally, following the comparison of NVD and SC groups, no significant difference in the RNFLT between two groups was detected (P>0.05). According to IOP measurements in both eyes, IOP during delivery was significantly higher than before and after delivery in NVD group (P=0.05 and P=0.048, respectively) and CS group (P=0.028 and P=0.035, respectively). In addition, IOP in NVD group was higher than CS group in all states, but no statistically significant difference was seen among them (P>0.05). Conclusion: In general, the results showed that delivery type does not significantly affect RNFLT and IOP. It is also possible that an increase in IOP will lead to different results in women with pre-existing glaucoma or risk factors for it. Therefore, in cases with a positive background of glaucoma, specialized examinations and delivery under the supervision of a specialist are recommended.