Due Date
The due date calculator (LMP — Last Menstrual Period method) estimates the day of birth as 280 days after the first day of your last period. Known as Naegele's rule, this is the standard reference used at the first obstetric visit. The HekimDoktor due date calculator factors in your cycle length for greater accuracy, saves the result to your profile, and opens week-by-week pregnancy tracking automatically.
How is it calculated?
Estimated Due Date = First day of last period + 280 days + (Cycle length − 28)
Why HekimDoktor?
- ✓Cycle-length adjustment (Naegele plus custom)
- ✓Result writes to User.pregnancyDueDate
- ✓Week-by-week pregnancy timeline opens automatically
Frequently Asked Questions
I don't remember my LMP — what should I do?
Enter an approximate date and wait for the dating ultrasound. A crown-rump length (CRL) measurement at 6–12 weeks gives a due date accurate to within ±5–7 days.
I have an irregular cycle — is the calculation reliable?
If your cycle differs significantly from 28 days (for example 32–35 days), Naegele's rule loses accuracy. HekimDoktor takes a cycle-length input and adjusts, but a confirmed date still requires an ultrasound.
Does the EDD matter for a planned C-section?
Elective caesareans are typically scheduled at 39 weeks (between 37 and 40). The estimated due date is the reference your doctor uses to plan the procedure.