It seems your wife has BP probably high BP ,this can produce blurring of vision secondary to 2 causes either BP itself (malignant hypertension
) or is it optic nerve ischemia
.She requires detailed
evaluation by neurologist
as optic nerve has been affected.She needs MRI brain with orbital cuts with contrast for confirming disease and to r/o demyelinating disorder and PRES.(Posterior reversible leucoencephalopathy common after pregnancy
associated with BP)Treatment plan depends on further clinical and radiological evaluation.Condition is treatable and immediate consultation needed.