A method used to determine when a pregnant woman is likely to go into labour, in which nine months and seven days are added to the date on which her last period started. If the woman does not have a 28-day menstrual cycle, an adjustment is made: e.g., if she has a 26-day cycle you would subtract 2 days from the Naegele’s estimated due date.
Method for calculating expected delivery date. Three months are subtracted from the first day of the last menstrual period and seven days added to that date.