Obstetrics and Gynaecology (often abbreviated to OB/GYN, O&G or Obs & Gynae) are the two surgical specialties dealing with the female reproductive organs, and as such are often combined to form a single medical speciality and postgraduate training program. This combined training prepares the practicing OB/GYN to be adept at the surgical management of the entire scope of clinical pathology involving female reproductive organs, and to provide care for both pregnant and non-pregnant patients.

In rural areas of the United States, particularly in areas west of the Mississippi River, it is not uncommon for general practitioners to offer obstetrical services to their patients. However, these generalists are most often not trained in the surgical aspects of obstetrics, nor have they been trained in gynaecology, and as such, they should not be confused with residency trained and board-certified OB/GYNs. All gynaecologists, therefore, are trained obstetricians, although the reverse is not necessarily true. However, some OB/GYNs may choose to drop the obstetric component of their practice and focus solely on gynaecology, especially as they get older. This decision is often based on the double burden of very late hours and, depending on the country, high rates of litigation.