Question 1

How is the pregnancy due date calculated from LMP?

Accepted Answer

Using Naegele's rule: add 280 days (40 weeks) to the first day of your last menstrual period (LMP). Or add 7 days to your LMP, subtract 3 months, and add 1 year. PingMeDoc's calculator does this automatically and shows your trimester timeline.

Question 2

What is EDD in pregnancy?

Accepted Answer

EDD stands for Estimated Due Date — the date your baby is expected to arrive, calculated as 40 weeks from your last menstrual period (LMP). Only about 5% of babies are born on their exact EDD. Most are born within 2 weeks before or after.

Question 3

How accurate is a due date calculated from LMP?

Accepted Answer

Due dates from LMP assume a regular 28-day cycle and ovulation on day 14. Accuracy is ±2 weeks. An ultrasound at 8–12 weeks provides a more accurate EDD. If your cycle is irregular, your doctor may adjust the EDD based on ultrasound measurements.

Question 4

When does each trimester start and end in pregnancy?

Accepted Answer

First trimester: weeks 1–12. Second trimester: weeks 13–26. Third trimester: weeks 27–40. PingMeDoc's due date calculator shows your current trimester, key milestones, and expected appointments.

Pregnancy Due Date Calculator

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