How to use our pregnancy calculator & important notes

Use this pregnancy calculator to work out how many weeks you have been pregnant. Input the date of your last menstrual period (which is the first day of your last period) and then click on the calculate button.

Please note that this calculator only estimates dates based on a 28 day menstrual cycle and might not be accurate for women whose cycle varies from that schedule. For more accurate estimates please speak with your doctor.

Pregnancy Calculator

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