We ask that you to fill your bladder by drinking a pint of water before the scan.
Five dating methods: LMP, FH, US and their combinations, were assessed against the actual day of delivery (ADD).
The main outcome measures were: (i) the days between the ADD and estimated date of delivery in pregnancies where spontaneous labour occurred and the baby had a normal birth weight; (ii) the incidence of gestational age-related outcomes; and (iii) the influence of clinical variables on dating discrepancies. The accuracy of dating was similar for certain and uncertain LMP. US-based dating was most accurate (for 85% of predictions within 14 days) and similarly accurate at 20 - 24 weeks and at Pregnancy dating by US, including those in more advanced pregnancies than currently permitted, is recommended since all non-ultrasound-based estimations of gestational age were considerably less accurate.
All pregnant women are offered an ultrasound scan at around 8-14 weeks of pregnancy. It's used to see how far along in your pregnancy you are and check your baby's development.
Your midwife or doctor will book you a dating scan appointment.
Whatever the reason, an early dating scan can give you peace of mind that all is well with your pregnancy and also ensure that you don’t miss out on the early first trimester screening tests that are available.