How Is the Due Date Calculated?

Hello, the estimated due date (EDD) can be calculated using several methods: 1. **Last Menstrual Period (LMP) Method**: Add 9 months (or subtract 3 months) to the month of the last menstrual period, and add 7 days to the date. 2. **Ultrasound Measurement Method**: Estimate gestational age based on fetal biometric measurements—including biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL). 3. **Quickening (First Felt Fetal Movement) Method**: Add 20 weeks to the date when fetal movement is first perceived, typically occurring between weeks 18–20 of pregnancy. 4. **Basal Body Temperature (BBT) Curve Method**: Determine ovulation timing from the BBT chart and calculate EDD accordingly. We hope this information is helpful. Wishing you a joyful and healthy pregnancy!