Pregnant when is my due date

Luckily, our handy pregnancy due date calculator can help you easily find out when your baby is due. How is my pregnancy due date calculated? Unless you've been tracking your ovulation, there's no way to know for sure exactly when you ovulated and conceived. That's why your due date is calculated based on the date of your last period instead. Most women ovulate about two weeks after the first day of their period, and conceive shortly afterwards.

The average pregnancy lasts between 37 weeks and 42 weeks. Our calculator uses this information to give you an estimated due date. Will my baby definitely be born on my due date? Unfortunately, no one can say for sure exactly when your baby will arrive. In fact, only about four per cent of babies are born on their due date!

But it is likely that your baby will arrive in the few weeks either side of your estimated due date. Knowing this can help you to be prepared for labour and birth, and to have everything ready for your new baby. Will my due date change when I have a scan? It may do. Your first pregnancy scan will probably happen when you're between 10 weeks and 14 weeks pregnant. To find your due date, enter the date of the first day of your last period, and select 'show your due date'.

Pregnancy normally lasts from 37 weeks to 42 weeks from the first day of your last period. You need to know the first day of your last period to use this calculator. If you do not know it or are unsure, speak to a midwife or GP. The educational health content on What To Expect is reviewed by our medical review board and team of experts to be up-to-date and in line with the latest evidence-based medical information and accepted health guidelines, including the medically reviewed What to Expect books by Heidi Murkoff.

This educational content is not medical or diagnostic advice. Use of this site is subject to our terms of use and privacy policy. Registry Builder New. Due Date Calculator When is your baby due? Use this pregnancy calculator to find your due date based on the date of your last menstrual period, conception date, IVF 3-day or 5-day transfer date or date of your last ultrasound.

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