Facing rising health care costs and competition from larger hospitals, the 240-bed San Gabriel Valley Medical Center has merged with Burbank-based UniHealth America, a network of nonprofit hospitals in Southern California.

Effective Oct. 1, the medical center will become the 12th hospital to join UniHealth America.

Makoto Nakayama, president and chief executive officer of the medical center, will retain his post under the agreement. He said the merger will free money to improve the hospital's outpatient services and preventive care, as well as to offer obstetrics services.