Second Lieutenant Carmen Lozano Dumler was born and raised in San Juan, Puerto Rico, where she also received her primary and secondary education. After graduating from high school, she enrolled in the Presbyterian Hospital School of Nursing in San Juan where she became a certified nurse in 1944. On August 21, 1944, she was sworn in as a second lieutenant and assigned to the 161st General Hospital in San Juan, where she received further training. Upon completing her advanced training, she was sent to Camp Tortuguero where she also assisted as an interpreter.