。
She goes to the hospital once a week.
Literal
She [topic-は] week [per-に] once hospital [to-に] goes.
病院に行く (to go to the hospital) is the standard Japanese expression for visiting a medical facility — unlike in English, 病院 covers everything from small clinics to large hospitals. The polite present 行きます describes a habitual action. Regular hospital visits suggest ongoing treatment or check-ups.