Due Date Calculator
Estimate pregnancy due date based on first day of the last menstrual period.
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What This Calculator Does
Estimate pregnancy due date based on first day of the last menstrual period.
It combines LMP Year, LMP Month, LMP Day, Cycle Length to estimate Estimated Due Date, Current Gestational Week.
Formula & Method
Notation used in the formulas: R = Estimated Due Date; x_{1} = LMP Year; x_{2} = LMP Month; x_{3} = LMP Day; x_{4} = Cycle Length.
Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.
Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.
Inputs Used
- LMP Year: Used directly in the calculation.
- LMP Month: Used directly in the calculation.
- LMP Day: Used directly in the calculation.
- Cycle Length: Used directly in the calculation.
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