Maternity & Obstetrics Naegele's Cycle-Adjusted Rule

Pregnancy Due Date (EDD) Calculator

Calculate your Estimated Date of Delivery (EDD), gestational age in weeks & days, current trimester, and key milestone scan dates.

Clinical Oversight: Dr. Prema Gunasekaran & Dr. Aarthi — Chief Obstetricians & Fertility Specialists
Interactive Calculator
Select the start date of your last normal bleeding
Standard cycle is 28 days (normal range: 21–35 days)
Specialist Oversight

Dr. Prema Gunasekaran & Dr. Aarthi

Chief Obstetricians & Fertility Specialists

Every pregnancy is unique. Timely milestone tracking, blood pressure vigilance, and ultrasound scans ensure healthy mothers and safe deliveries.
Schedule an Appointment

Clinical Basis

Naegele's Rule calculates delivery date by adding 1 year and 7 days to the first day of the Last Menstrual Period (LMP), subtracting 3 months, and adjusting for cycle variation (+/- days from standard 28-day cycle).

Reference Guidelines

  • First Trimester (Weeks 1–12): Organogenesis phase. Key milestones: Dating scan (7–9 weeks), Dual marker & NT scan (11–13+6 weeks), daily folic acid supplementation.
  • Second Trimester (Weeks 13–27): Golden trimester. Key milestones: Comprehensive TIFFA / Anomaly scan (18–20 weeks), fetal movement awareness, tetanus toxoid vaccination.
  • Third Trimester (Weeks 28–40): Fetal growth and maturity. Growth ultrasound & Doppler scans, weekly/bi-weekly antenatal check-ups, delivery planning.

Related Health Calculators

Explore other specialized clinical assessment tools for your care.