Corneal Topography and High Order Aberrations in Regular Contraceptive Pills

Inclusion Criteria: * Female participants aged 18-40 years. * Prescribed combined oral contraceptive pills as part of routine gynecological care. * Willing to undergo corneal topography/tomography before starting treatment and after 1 year. * No previous history of corneal disease or ocular surgery. * Able to provide informed consent. Exclusion Criteria: * Keratoconus or suspected corneal ectasia. * Corneal opacity, dystrophy, degeneration, or scarring. * Previous ocular surgery or significant ocular trauma. * Current contact lens use or recent contact lens use without adequate discontinuation period. * Active ocular surface disease or severe dry eye. * Glaucoma, uveitis, retinal disease, or other significant ocular pathology. * Diabetes mellitus, autoimmune disease, thyroid disease, pregnancy, or lactation. * Use of other hormonal therapy or systemic medications known to affect corneal parameters.