Doctors who specialize in delivering babies are called obstetricians. Most of them also specialize in gynecology, the study of women's health, and are commonly referred to OB-GYNs. A physician in a sub-specialty of this field who concentrates on high-risk pregnancies and deliveries is called a perinatologist.
Obstetricians spend four years after medical school studying women's health issues, including the management of pregnancy and delivery. Becoming a maternal-fetal specialist, or perinatologist, requires an additional two or three years of specialization in the field. Doctors who specialize in family practice are also trained to deliver babies. They typically manage only low-risk pregnancies and deliveries.