Impact of myopic laser surgery and pregnancy-related hormonal fluctuations on corneal biomechanics.

OBJECTIVE

To investigate dynamic changes in corneal biomechanics during pregnancy and their effects on the outcomes of myopic laser surgery.

METHODS

A total of 100 women with early intrauterine singleton pregnancies and a history of high myopia were enrolled and divided into two groups according to prior myopic laser surgery. Fifty-three participants who had undergone myopic laser surgery comprised the observation group, and 47 without laser surgery comprised the control group. Corneal biomechanical parameters, including applanation times, deformation amplitude, and central corneal thickness (CCT), were measured using the Corvis ST system at three time points, namely, pre-pregnancy, during pregnancy, and six weeks postpartum. Ophthalmic biometric indices (CCT, corneal curvature, axial length, and intraocular pressure (IOP)) were also taken. Further, serum concentrations of estrogen, progesterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, and prolactin were assessed to evaluate hormonal effects on corneal changes. Logistic regression was used to identify factors influencing CCT, with particular attention to the roles of laser surgery and hormonal variation.

RESULTS

Uncorrected visual acuity (UCVA), corneal biomechanics, and ocular biometry varied significantly over pregnancy. The observation group achieved greater UCVA improvement compared to the control group, particularly at 6 and 9 months of gestation (P < 0.001). Notably, the Observation Group exhibited significant reductions in CCT and corneal curvature from the third month of pregnancy to six weeks postpartum (P < 0.05). Logistic regression identified prior laser surgery and estrogen levels as independent predictors of CCT, with laser surgery showing the strongest association (OR = 0.935, P < 0.001).

CONCLUSIONS

Myopic laser surgery and hormonal fluctuations during pregnancy exert significant effects on corneal biomechanics, particularly on central corneal thickness and corneal curvature.