Pregnancy Due Date Calculator - Calculate Baby Due Date

Pregnancy due dates are calculated using Naegele's rule, which adds 280 days (40 weeks) to the first day of your last menstrual period. This method assumes a 28-day menstrual cycle with ovulation occurring on day 14.

How Accurate Are Due Dates?

• Only about 5% of babies are born on their exact due date
• Most babies (90%) are born within 2 weeks of the due date
• First-time mothers often deliver 1-2 days after their due date
• Ultrasound dating in early pregnancy is more accurate than LMP dating

Pregnancy Milestones

• Week 4: Missed period, pregnancy test positive
• Week 8: First prenatal appointment
• Week 12: End of first trimester, reduced miscarriage risk
• Week 20: Anatomy scan, gender reveal possible
• Week 28: Third trimester begins
• Week 37: Full-term pregnancy begins

When to Contact Your Healthcare Provider

Schedule your first prenatal appointment around 8-10 weeks of pregnancy. Contact your provider immediately if you experience severe cramping, heavy bleeding, or other concerning symptoms during pregnancy.