This website is intended for healthcare professionals.
Subscriber log in
Trial log in

Operative vaginal delivery

Extracted from Survival Guide to Midwifery, 2nd Edition (2012) Diane M. Fraser and Margaret A. Cooper, Oxford; Churchill Livingstone: 2012. Courtesy Elsevier

Assisted or operative (instrumental) vaginal delivery is used when the mother is unable to give birth without medical or surgical assistance. Assisted vaginal birth is a widely practised intervention, accounting for approximately 11 per cent of births in the UK, and 15% in Australia and Canada. Women who use epidural analgesia are at increased risk of having an instrumental assisted birth.

Forceps are most commonly used to expedite the birth of the head, or to protect the fetus or the mother or both from trauma and exhaustion. Forceps are also used to assist the delivery of the after-coming head of the breech.

Obstetric forceps are composed of two separate blades, right and left, that are inserted separately on each side of the head and then locked together. The blades are spoon shaped (cephalic curve) to accommodate the form of the baby's head.

Forceps deliveries fall into two categories, low and mid-cavity. High cavity forceps are now considered unsafe and a caesarean section will be carried out instead.

The main indications for a forceps delivery are delay in the second stage of labour, fetal compromise, and maternal distress.

Prior to forceps delivery, ensure:

  • The woman's bladder is empty to prevent injury;
  • Adequate analgesia is provided (epidural or pudendal block plus perineal infiltration of local anaesthetic
  • Information is given and consent obtained
  • Paediatrician or advanced neonatal practitioner is informed and available if required
  • Neonatal resuscitation equipment is checked and prepared in case it is necessary

Ventouse method

The ventouse vacuum extractor is an instrument that applies traction. It can be used as an alternative to forceps. The cup clings to the fetal scalp by suction and is used to assist maternal effort. It may be used when there is a delay in labour, when the cervix is not quite fully dilated. It may also be useful in the case of a second twin, when the head remains relatively high.


  • The woman is usually in the lithotomy position; the same precautions should be observed as for a forceps birth
  • The cup of the ventouse is placed as near as possible to, or on, the flexing point of the fetal head
  • The vacuum in the cup is gradually increased to achieve close application to the fetal head, usually to 0.8kg/cm2
  • When the vacuum is achieved, traction is applied with a contraction and with maternal effort. Traction is applied downwards and backwards, then forwards and upwards, following the natural curve of the pelvis.
  • The vacuum is released and the cup is removed at the crowning of the fetal head.
  • The mother can then push the baby for the final part of the birth.


Prolonged traction will increase the likelihood of scalp abrasions, cephalhaematoma and subaponeurotic bleeding.

Further reading

Royal College of Obstetricians & Gynaecologists (2011) Operative vaginal delivery. Green-top guideline No 26. Available at:

Return to index