Vital Records and Health Statistics - Epidemiology Report
January 27, 2017
The national standard for estimating gestational age of newborns, until recently, relied on the interval between the first day of the mother’s last normal menstrual period and the date of birth. Beginning with 2014 national birth data released in December 2015, the National Center for Health Statistics transitioned to the obstetric estimate of gestation defined as the birth attendant’s final estimate of gestation at delivery.