Let NUGA keep count for you
Enter your due date once. NUGA follows your week, and the day before each appointment it gathers what you've noted and the questions to bring.
Download on the App Store Available nowHow is a due date worked out?
The usual method counts 280 days (40 weeks) from the first day of your last period. Pregnancy is counted from then, not from conception, which is why you're already "two weeks pregnant" around the time you conceive. If your cycle is longer or shorter than 28 days, the date moves by the difference.
From a conception date it's 266 days. From an IVF transfer it's 261 days for a 5-day embryo and 263 days for a 3-day embryo.
How accurate is it?
It's an estimate. Only around 1 in 25 babies arrive on their due date; most come in the two weeks either side of it. Think of it as the middle of a window, not an appointment.
Why is my scan date different?
An early ultrasound measures your baby directly, so if it gives a different date from your period, providers often go by the scan. If you've been given a date, choose I already know my due date above to see where you are.
Sources
This page draws on public guidance from:
General information, not medical advice. Your midwife or doctor will confirm your due date, usually at your first scan.