Pregnancy Calculator
Work out your due date and how far along you are, then see roughly when each of your antenatal appointments and scans on the Isle of Man should fall. Nothing you enter leaves your device; your dates are remembered in this browser so they are here next time.
How it works
Pregnancy is counted from the first day of your last period, not from conception, so at conception you are already about two weeks pregnant. Your due date is 40 weeks (280 days) after that first day, assuming a 28-day cycle. A longer or shorter cycle moves it later or earlier by the difference (NHS due date calculator).
If you have had a dating scan, the date it gives is more reliable than one worked out from your period, and it is the one your midwife will use. Only around one baby in twenty is born on its due date; most arrive between 37 and 42 weeks (NHS trust guidance).
This is an estimate for information only. Self-referral, booking and scan timings follow the usual Isle of Man pathway described in our antenatal care guide; the hospital bag and 41-week entries are general NHS advice. Your own timings may differ. Always follow the advice of your midwife or GP.
Sources
Last checked 19 October 2026
- Due date calculator — NHS
- Pregnancy week by week (trimesters) — NHS
- Your antenatal appointments — NHS
- Due date calculator — NHS 111 Wales
- Baby due dates and how they affect my care — Royal Berkshire NHS Foundation Trust
- Jane Crookall Maternity Unit (self-referral at 6 to 7 weeks) — gov.im
- Jane Crookall Maternity Unit: self-referral at 6 to 7 weeks — gov.im (booking and scan timings are typical UK timings; your midwife will confirm yours)
The scan windows shown (11 to 14 and 18 to 21 weeks) are the NHS ranges; Isle of Man pages say “around 12” and “around 20” weeks. Some gov.im pages block automated checking, so confirm on the page itself.