Pregnancy Week Counter Calculator

Last Menstrual Period LMP Pregnancy Week Counter Explanation and Clinical Context Pregnancy Week Counter is a practical clinical tool used to estimate gestational age based on the first day of the Last Menstrual Period. This approach follows the Naegele principle in which pregnancy age is counted from the first day of the LMP and is widely applied in obstetric care. Accurate calculation of gestational age helps clinicians understand fetal development timing assess pregnancy progression guide prenatal monitoring and determine the timing of screening tests and interventions.

Gestational age is normally expressed in completed weeks and additional days and is essential for interpreting fetal growth ultrasound findings and maternal evaluations. The tool supports clinical decision making by providing a simple standardized estimation method when early ultrasound data is not yet available.