At what point do forceps delivery happen?

A forceps delivery or ventouse vacuum extraction is usually only used to help the baby out in circumstances of fetal distress or maternal exhaustion. Sometimes the baby is slightly malpositioned, perhaps with a deflexed head (as if the baby was looking up, most commonly with epidurals). Sometimes the second stage of labour can go on too long and it becomes obvious, even with full dilatation, good contractions and effective pushing, that the birth is too challenging, and assistance is wise. Some instrumental deliveries require significant assistance, and others are really just needing a ‘bit of a lift out’.