ABSTRACT
DIFFERENTIAL DIAGNOSIS Abnormal Lie The foetal lie describes the position of the baby in relation to the longitudinal axis of the uterus. The foetus can be described as having a longitudinal, transverse or oblique lie. If the foetus is in a longitudinal lie, it can either be a breech or cephalic (head palpable in the pelvic inlet) presentation. In the oblique position the foetus’s head or buttock can be palpable in either iliac fossa. In the transverse lie, the baby lies across the uterus with the head palpable in the fl ank and the pelvic inlet remaining empty. An abnormal lie is considered to be any position held by the foetus that is not parallel to the long axis of the uterus. Before 36 weeks an abnormal lie is common and is not predictive of the lie or presentation at the time of labour. On the other hand, an abnormal lie after 36 weeks is more likely to persist at the time of labour. It occurs in 0.5% of all pregnancies and is associated with pre-term labour, multiparity, multiple pregnancies (twins), polyhydramnios and placenta praevia. An abnormal lie is regard as safe before 37 weeks with the baby able to spontaneously progress to a longitudinal lie before labour. Beyond 37 weeks, an ultrasound should be carried out with a view to performing a Caesarean section.
