Malpositions and malpresentations of the fetal head

Nearly 95% of fetuses at term present with the vertex (an area subtended by the two parietal eminences and the anterior and posterior fontanelles). With vertex presentation, the vast majority of women progress well in labour and have spontaneous vaginal delivery. Any presentations other than vertex can lead to difficulties in labour and hence are called as malpresentations. Malpresentations of fetal head occur due to extension of the fetal head causing brow or face to present in labour. Malpositions of fetal head result when the occiput persists in a lateral or posterior position. Malpresentations and malpositions of fetal head are usually diagnosed in labour and are associated with difficult labour and increased risk of operative intervention. Regular systematic clinical examinations to monitor progress of labour and fetal wellbeing are necessary once the diagnosis is confirmed. Although vaginal delivery is possible in many cases, Caesarean section becomes necessary when the malposition or malpresentation persists and labour fails to progress.