Skip to content
ClinCalc Pro
Menu
obstetrics obgyn

Estimated Date of Delivery (Naegele Rule)

Calculates weeks remaining to EDD from last menstrual period using the Naegele rule (LMP + 280 days).

Score interpretation

Post-dates or at term

→ Assess for induction; CTG and amniotic fluid index

Term (37-40 weeks)

→ Birth plan; group B strep screen; antenatal classes

Antenatal period

→ Routine antenatal care; anatomy scan at 18-20 weeks

Interpretation bands for the EDD Calculator. Apply clinical judgement and local guidance.

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.