children s health issues
Overview of General Problems in Newborns
Gestational Age
Gestational age refers to the number of weeks of pregnancy. Many issues that affect newborns are related to the gestational age because it reflects the newborn's degree of physical maturity at birth. The gestational age is determined by counting the number of weeks between the first day of the mother's last menstrual period and the day of delivery. This time frame may be adjusted according to other information doctors receive, including the results of early ultrasound scans, which give additional information regarding the gestational age. The estimate of the date a baby will be born (due date) is set at a gestational age of 40 weeks. The due date is an estimate, and only a small number of babies are born on that exact date. Most babies are born within a few weeks before or after the due date. Newborns are classified by gestational age as Preterm (Premature) Newborns : Delivered before 37 weeks of gestation Full term: Delivered at 37 to before 42 weeks of gestation Postterm Newborns : Delivered at 42 weeks or more of gestation Doctors also use the results of a physical examination and the physical features of the newborn (see sidebar Physical Features of a Premature Newborn ) to confirm gestational age. 