Accurate dating of pregnancy is crucial for determining gestational age. BMUS guidelines state that the most accurate measurement for dating a pregnancy is a crown rump length, taken between 7 and 13 weeks gestation.1 Pregnancies without ultrasonic examination before 25+1 weeks should be considered sub-optimally dated.
Booking late is known to be associated with poorer obstetric and neonatal outcomes. These women often have complex social issues.
No established guideline currently exists to advise on the antenatal management of these women. This guideline aims to standardise current antenatal practice.