Determining gestational age, often measured in units of seven days, is a cornerstone of prenatal care. This process enables healthcare providers to track fetal development, schedule appropriate screenings, and anticipate a delivery timeframe. For example, an assessment at “20 weeks” indicates that approximately half of the typical gestation period has elapsed.
Accurate gestational dating offers several advantages. It facilitates timely interventions if developmental concerns arise and allows for informed decisions regarding delivery methods. Historically, reliance on a woman’s last menstrual period served as the primary method. However, contemporary practices integrate ultrasound measurements, particularly during the first trimester, to improve precision and account for variations in menstrual cycles.