This review of 32 studies (6597 women) looks at assisted or instrumental vaginal deliveries in women in the second stage of labour. The importance of this review is due to the fact that Instrumental delivery is a frequent intervention in childbirth and in some cases may result in harmful outcomes for either mother or baby or both.
The main comparisons are between the forceps or the ventouse. There are also comparisons between different types of ventouse. The outcomes which are analysed are the success of the particular instrument in achieving the delivery and the rate of complications for both mother and baby. Not all studies considered all outcomes, and in particular, there were differences in the types of complications encountered by mothers and babies. In addition, we identified no studies for some comparisons.
The results showed that the forceps was the better instrument in terms of achieving a successful delivery. However, it was also associated with higher rates of complications for the mother. These were perineal trauma, tears, requirements for pain relief and incontinence. There were risks of injury to the baby with both types of instrument.
Comparisons between different types of ventouse revealed that the metal cup was better at achieving successful delivery than the soft cup,.but with more risk of injury to the baby. There were no significant differences between the handheld and the standard vacuum.
Decisions as to which instrument is best will, therefore, depend upon individual situations where the urgency with which the baby needs to be delivered will be balanced against potential risks to the mother and baby.