About Pregnancy Due Date Calculator
When to Use
- Initial prenatal visit
- Pregnancy confirmation
- Planning prenatal care schedule
- Tracking pregnancy milestones
- Birth planning and preparation
Pearls/Pitfalls
- Only 5% of births occur on due date
- Normal range is ±2 weeks
- Early ultrasound most accurate
- LMP may be unreliable
- Consider cycle length variations
Why Use
- Estimate delivery date
- Track fetal development
- Plan prenatal care
- Schedule screening tests
- Monitor pregnancy progress
About Pregnancy Due Date Calculation
Understanding Due Date Calculation
The estimated due date (EDD) is calculated using Naegele's rule, which adds 280 days (40 weeks) to the first day of the last menstrual period (LMP). This calculation assumes a regular 28-day menstrual cycle.
Key considerations:
- Gestational age starts from LMP
- First trimester: weeks 1-13
- Second trimester: weeks 14-26
- Third trimester: weeks 27-40
- Term pregnancy: 37-42 weeks
Important Safety Information
This calculator is intended for healthcare professionals only. Opioid medications carry significant risks including addiction, overdose, and death. Always follow your local prescribing guidelines and regulations.
According to CDC guidelines, starting doses should generally be below 50 MME/day, and increasing to ≥50 MME/day increases overdose risk without necessarily improving pain control.