Management of malposition and malpresentation in labour

Abstract

A malpresentation is diagnosed when any part of the baby is presenting to the maternal pelvis other than the vertex of the fetal head. A malposition is diagnosed when the fetal head is in any position other than occipito-anterior (OA) flexed vertex. Both malpresentation and malposition are associated with prolonged or obstructed labour, fetal and maternal morbidity, and potential mortality, if not managed in labour effectively. Malpresentations can be further classified by the lie of the fetus, be it normal or abnormal. The most common fetal malpresentation in longitudinal lie is breech presentation which itself can be further subdivided into subtypes. Other malpresentations in longitudinal lie include face, brow and compound. The fetus in non-longitudinal lie may be oblique or transverse, with shoulder, arm or cord presentations. Malpositions, such as occipito-posterior (OP) and occipito-transverse (OT), can be further described by the degree of deflexion and asynclitism. This practical review considers the potential fetal abnormal presentations and positions, their risk factors, and how these should be managed during labour.