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如何计算Due Date Calculator

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A due date calculator uses your last menstrual period (LMP) to predict when your baby will be born. The standard method (Naegele's Rule) adds 280 days (40 weeks) to the LMP. Due dates are estimates — only 4% of babies arrive on the exact predicted date.

分步指南

  1. 1Record the first day of your last menstrual period
  2. 2Add 280 days (or 9 months and 7 days) to get your due date
  3. 3Key milestones: conception ~day 14, heartbeat ~week 6, anatomy scan ~week 20
  4. 4Full term: 37–40 weeks; induced if past 41–42 weeks

例题解析

输入
LMP: March 1
结果
Due date: December 6
Add 280 days
输入
LMP: July 15
结果
Due date: April 21 (next year)
Full 40-week calculation

设置

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