1. A subspecialty of obstetrics concerned with the care of the mother and fetus at higher-than-normal risk for complications: Since Kitty loved babies and little children she decided to study perinatology and work as a doctor later on.

Since the perinatal period, depending on the definition, starts at the 20th to 28th week of gestation and ends one to four weeks after birth, perinatology logically could be an obstetrical and pediatric subspecialty, but in practice, it is part of obstetrics.

The comparable area of pediatrics is "neonatology". A high-risk baby might be cared for by a "perinatologist" before birth and by a "neonatologist" after birth.
2. Etymology: The word perinatology is a linguistic combination of the Greek peri-, "around" or "about" plus natal from the Latin natus, "born" plus ology from the Greek logos, "treatise" or "study of".