Pregnancy Calculator

Congratulations on your Pregnancy!

Pregnancy calculatorWork out your due date with this calculator. Remember it is the date of the first day of your last menstrual period (i.e. the first day of vaginal bleeding) that you should enter:


However, did you know that only approximately 5% of babies are born on their due date!

An ultrasound scan early in the pregnancy (<12 weeks) is very useful for accurate dating, especially if you are not certain about the date of your last menstrual period, or if your periods are irregular.  The accuracy of a transvaginal scan <12 weeks gestation has an accuracy of +/- 5 days.

As the pregnancy progresses, the accuracy of ultrasound scans for dating diminishes.  At the morphology scan between 18-20 weeks gestation, the accuracy of the scan for dating is +/- 2 weeks.  This is because every baby grows at different rates, and as the baby has had more time to grow, there can be more individual variations in size.  Therefore, whilst the morphology scan may indicate a different due date to your original due date, the agreed due date established at your booking in visit will not be altered by the morphology scan dating.

Early pregnancy ultrasound can be useful for dating the pregnancy and working out the due date of the pregnancyTo discuss this further, and to book in with  for your management of your pregnancy and delivery at Greenslopes Maternity, click on the “Make a Booking” button at the top of the page, and note any preferred times for your appointment. One of Dr Law’s secretaries will contact you to confirm your appointment.

Alternatively, call 1300 464 464 to make an appointment.

Greenslopes Obstetrics and Gynaecology