The estimation of gestation duration is a fundamental aspect of prenatal care. It involves determining the expected date of delivery, often based on the first day of the woman’s last menstrual period, ultrasound measurements, or conception date when known. For example, using Naegele’s rule, one calculates the estimated due date by adding one year, subtracting three months, and adding seven days to the first day of the last menstrual period.
Accurate dating of pregnancy is crucial for several reasons. It allows healthcare providers to monitor fetal growth and development, schedule appropriate prenatal tests, and plan for labor and delivery management. Historically, the reliance was primarily on menstrual history. However, modern techniques like ultrasound offer more precise dating, especially in early pregnancy, impacting the timing of interventions for high-risk pregnancies and reducing the incidence of prematurity.
