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Enter the date of the first day of your last menstrual period or if you have been given a due date please enter it here Predictions from scans at around 12 weeks are extremely accurate
Use the calendar to select your date by clicking on the correct day, if you need a date in previous months just click the arrow in the top left to go back a month
Enter the average number of days between the start of your periods. If your periods are irregular use the average 28 day cycle
The advanced calculation uses the latest medical research to produce a more accurate due date for natural spontaneous delivery, tailored to your circumstances. If you select the standard option we employ a simpler method often used by more primitive calculators
Whether your period is regular or irregular has a statistical impact upon the likely birth date of your child. Please select the applicable option
Maternal age does have an impact upon the likely birth date of a child. Please select your age group from the menu
Enter the number of children you have had before since this has a significant effect on the likely birth date
This is not compulsory. Enter the ethnicity of the mother here. Although this might appear to be an intrusive question it does have significant effect on the due date
This is not compulsory. Enter the ethnicity of the father here. Although this might appear to be an intrusive question it does have significant effect on the due date