All physicians first complete medical school (MD, MBBS, or DO). To become primary care physicians, medical school graduates then undertake postgraduate training in primary care programs, such as family medicine (also called family practice or general practice in some countries), pediatrics or internal medicine. Some HMOs consider gynecologists as PCPs for the care of women, and have allowed certain subspecialists to assume PCP responsibilities for selected patient types, such as allergists caring for people with asthma and nephrologists acting as PCPs for patients on kidney dialysis.