Naegele's Rule is a widely accepted method of calculating a woman's estimated date of delivery (EDD) in pregnancy. It is based on the assumption that a woman's menstrual cycle is regular and lasts for 28 days, with ovulation occurring on day 14. However, there are various other terms used for Naegele's Rule, such as "EDD by last menstrual period", "LMP-based EDD", "Gestational Age by LMP", and "Rule of Forty". These terms all refer to the calculation of EDD by counting back 3 months from the first day of the last menstrual period and adding 7 days. Despite its limitations, Naegele's Rule remains a valuable tool for estimating EDD and managing pregnancy.
