Pre hospitalization coverage refers to the coverage of any expenses incurred by the policyholder before the hospitalization. Common costs like a consultation, diagnostics, etc., that have occurred during a fixed period of time before the hospitalization can be covered.
Post hospitalization coverage refers to the coverage of expenses incurred after the policyholder has been discharged from the hospital. For ex, common instances like follow-ups, tests, and medicines fall under post-hospitalization coverage.
Read more about pre and post hospitalization here.