O&G may refer to: Obstetrics and gynaecology, surgical specialties dealing with the female reproductive organs Obstetrics & Gynecology (journal), a scientific journal of the American College of Obstetricians and Gynecologists O&G (magazine), a magazine published by the Royal Australian and New Zealand College of Obstetricians and Gynaecologists Oil and gas, hydrocarbons extracted from the subsurface