The Lohja Hospital Area comprises the municipalities of Karkkila, Lohja, Siuntio, and Vihti. The population of the area's municipalities is approximately 91,000. There is one hospital in the area, Lohja Hospital.
Lohja Hospital provides emergency medicine and it is also a maternity hospital. It is on call 24 hours a day and provides and acquires specialist medical care for the residents of the municipalities in its area, or for residents of other areas in accordance with an agreed distribution of work.
The hospital has arranged 24-hour specialist medical care and primary health care joint emergency service with the City of Lohja. The hospital also serves as a teaching hospital.