What is the best way to calculate due date and estimate delivery date?
* It is really complicated. The simple calculations listed below based on a fixed addition from your last menstrual period or those used by most online calculators are terribly inaccurate. A lot of recent research has indicated a number of other variables to consider. (See the page links, further down this page, listed under Related Links). * This is how to calculate your due day. The due month is: your LMP month + 9. The due date is: your LMP date plus 7. For example, if your LMP was 3/10/95: 3 + 9 = 12 (Dec), 10 + 7 = 17 (17th day). If the added month exceeds 12, then you subtract 12. For example, if you LMP was 6/20/95, the month will be (6 + 9) – 12 = 3 (March), and the date will be 20 + 7 = 27, so your due date will be 3/27/96. * There are loads of methods and calculators out there but their accuracy is limited. * I was always taught -3 +7, if your LMP was 10/11 you -3m= 7/11 and add 7d= 7/18. * You can always use an on-line due date calculator. See the page links, further down th
