Question 1

How is my due date calculated?

Accepted Answer

Your due date is calculated using Naegele's rule: add 280 days (40 weeks) to the first day of your last menstrual period (LMP). If you know your conception date, add 266 days (38 weeks) instead. This gives an estimated due date — only about 5% of babies arrive on their exact due date.

Question 2

How accurate is a due date calculator?

Accepted Answer

A due date calculator gives an estimate. Most babies are born within 2 weeks either side of their due date (between 38 and 42 weeks). Your 12-week dating scan may adjust your due date if the baby's measurements suggest a different conception date. The scan date is generally considered more accurate than LMP-based calculation.

Question 3

What appointments do I need during pregnancy in Australia?

Accepted Answer

Key appointments include: booking visit with GP or midwife (6-8 weeks), combined first trimester screening and dating scan (11-13 weeks), morphology scan (18-20 weeks), glucose tolerance test for gestational diabetes (24-28 weeks), Group B Strep test (35-37 weeks), and regular antenatal visits increasing in frequency as you approach your due date.

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