“Completed” Gestational Weeks?

Historically, governmental and professional societies referred to gestational "completed" weeks in their definitions of preterm or term deliveries. But this term of "completed weeks" has remained a point of confusion for clinicians and researchers alike. The ACOG favors simply stating the gestational age as clear designations of weeks and days (e.g., 34 weeks 5 days) rather than "completed weeks". Nonetheless, state and national vital statistics reports still rely on documented completed weeks. Does "34 completed weeks" imply the day after 33 weeks and 6 days, or the day after 34 weeks and 6 days"? We'll clear up the confusion regarding "completed" weeks of gestation in this episode.