The countdown to baby's arrival
If you've taken a pregnancy test at home and it has given a positive result, you will probably be frantically trying to work out your due date ahead of having your dating scan (as well as leaping up and down with joy and grinning from ear to ear, of course!).
At a glance
- Pregnancies usually last from 37 weeks to 42 weeks
- To work out your due date, you need to count 40 weeks from the first day of your last period
Pregnancies usually last from 37 weeks to 42 weeks, and your baby's expected day of arrival is worked out from the first day of your last period (so if you took a test on the first day you were late and it was positive, it would be about two weeks after your baby's conception).
Home pregnancy tests
You can get a result from a regular home pregnancy test as early as the day after your period is due, so if you have a very regular cycle and can pin point the day you are due on, you could work out your date fairly accurately. In fact, some ultra sensitive tests can be used before you've even missed a period, from as early on as eight days after conception.
Working out your due date
To work out your due date, you need to count 40 weeks from the first day of your last period. You could even try working out your date from when you think you conceived – tricky for most women as they won't know exactly when they ovulated!
Obviously your dating scan at the hospital will give you an accurate due date for your baby, but you can have some fun trying to work it out before you have it (usually at around 10 weeks).