Medicaid, a system originally created to provide medical assistance to women and children in poverty, today spends about one-third of its budget on the elderly.
Literal
Originally [topic-は], poverty-class [possessive-の] women [and-や] children [target-に] medical-protection [object-を] provide [purpose-ために] created system [copula-である], America low-income medical-assistance system [subject-が], today [topic-では], that budget [possessive-の] approximately one-third [object-を] elderly [target-に] is-spending.
A dense, multi-layered sentence typical of formal news or academic writing. The appositive clause (本来は…制度である) sits between the topic and the main predicate, providing background before the main point. 約３分の１ ('approximately one-third') uses the fraction pattern ~分の~.