Obstetrics: the field of study concentrated on pregnancy, childbirth, and the postpartum period. As a medical specialty, obstetrics is combined with gynaecology under the discipline known as obstetrics and gynaecology (OB/GYN) which is a surgical field. Your obstetrician can take care of you throughout your pregnancy, and give you follow-up care such as annual Pap tests for years to come.