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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.

Guide étape par étape

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

Exemples résolus