Pregnancy calculation is the process of estimating how far along a pregnancy is and determining the expected due date. Most healthcare providers calculate this starting from the first day of the last menstrual period (LMP), adding 40 weeks (about 280 days) to estimate the baby’s arrival. This method is commonly supported by guidelines from organizations like American College of Obstetricians and Gynecologists. In some cases, an early ultrasound may be used to confirm or adjust the estimated due date for greater accuracy. Understanding pregnancy calculation helps parents track fetal development, schedule prenatal visits, and prepare for each stage of pregnancy with confidence.
