When am I due?

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One of the first questions to come to mind when staring at a positive pregnancy test is “when am I due?”.

Mike Rohde's Custom Moleskine Planner
Put the date in the diary!Mike Rohde / Foter / CC BY-NC

So, without an immediate trip to a doctor how do you know when you are due?

Pregnancy is known as 40 weeks from the first day of a women’s last period – LMP – Last Menstural Period. So if you know when your last period was then it is easy peasy to work out an Estimated Due Date (EDD) by just adding 40 weeks and you have your date.

So, if your period was 7th March 2010 then your due date would work out at 12th December 2010.

Another method of calculating your EDD is to roll forward 9 months and then add 7 days.

Taking the same example, adding 9 months and 7 days to 7th March 2010 results in a due date of 14th December 2010.

Without knowing the date of your last period the main way to calculate your due date is via ultrasound scan. An early scan (pre 12 weeks) can result in a more accurate due date.

Finally, some women will know the date on which they had intercourse which resulted in the pregnancy. By adding 38 weeks to this date can give a due date. However, it must be born in mind that while you may know the date of intercourse, conception may not occur for up to 5 days as the sperm waits for an egg to fertilise.

All of that said, the dates that are calculated are just estimates. No matter how accurate a date you think you have baby will come when it’s good and ready and only a small portion arrive on their EDD – which is likely just co-incidence anyway!

To find your EDD check out our easy to use online calculator