The phrase ‘operative delivery’ is used to describe both instrumental vaginal delivery and caesarean section. It may be indicated to expedite delivery in the presence of fetal distress, or for ‘delay’ or failed progress, despite good contractions and maternal effort. The choice between instrumental delivery and caesarean depends partly on the stage of labour, with instrumental delivery possible only in the second stage; even then, specific criteria must be met. Caesarean section can be used in both the first and second stages of labour and after a failed or abandoned attempt at instrumental delivery.

A careful assessment is required prior to instrumental delivery, beginning with abdominal palpation. There should be no head palpable above the symphysis pubis although occasionally one-fifth is palpable in occipitoposterior positions. One of the most difficult parts of an instrumental delivery is being completely certain of the fetal head position prior to applying the forceps or ventouse (also known as vacuum-device). A systematic examination should determine the orientation of both the anterior and posterior fontanelles as the most common mistake is diagnosing an occipitoanterior position when in fact it is occipitoposterior. If there is a suspicion from palpation of the sutures that the fetal head is occipitotransverse, it is often helpful to try to feel for an ear anteriorly under the symphysis pubis. Some obstetricians use transabdominal ultrasound to confirm the position of the fetal head, others will seek a second opinion, or re-examine the patient in an operating theatre with good anaesthesia, where early recourse to caesarean section is possible. Incorrect assessment of the fetal head position or station results in a higher rate of failed instrumental delivery and morbidity for the mother and baby.

Operative vaginal delivery requires a multidisciplinary approach to maximize the likelihood of success and minimize maternal and fetal trauma. In addition to the attending midwife, a practitioner experienced in neonatal resuscitation should be present and the anaesthetist is frequently involved in the provision of adequate analgesia. Umbilical artery and vein acid–base status should be routinely recorded immediately after delivery.

The choice is between forceps and the ventouse.