Gestational Age Designations Redefined for Term Deliveries
The standard medical definition of a term pregnancy has changed to eliminate the assumption that neonatal outcomes are uniform across the final weeks of gestation. The American College of Obstetricians and Gynecologists reported that the traditional three-week window before and two-week window after an estimated delivery date no longer accurately reflects infant health risks, particularly respiratory morbidity.
New Gestational Age Terminology Established in 2012
A specialized work group convened in late 2012 to address the lack of uniformity in how clinicians categorize deliveries occurring at or beyond 37 weeks of gestation. The group established four distinct subcategories to replace the broad label of term pregnancy.
- Early term: 37 0/7 weeks of gestation through 38 6/7 weeks of gestation.
- Full term: 39 0/7 weeks of gestation through 40 6/7 weeks of gestation.
- Late term: 41 0/7 weeks of gestation through 41 6/7 weeks of gestation.
- Postterm: 42 0/7 weeks of gestation and beyond.
Research demonstrates that neonatal outcomes vary significantly within the original five-week range, making these precise designations necessary for tracking clinical data and infant health.
Endorsement by Major Obstetric Organizations
The Society for Maternal-Fetal Medicine and The American College of Obstetricians and Gynecologists formally endorse these updated definitions. Both organizations encourage clinicians, researchers, and public health officials to adopt the standardized terminology uniformly. This transition aims to improve data reporting accuracy, facilitate targeted clinical research, and support the delivery of higher-quality health care for mothers and newborns.
Related reading