Delay in Second Stage of Labour and Use of Forceps

The rate of operative vaginal delivery has remained fairly constant at 10-15%.¹
Although it is now generally well established that there are significant risks associated with rotational and mid-cavity deliveries,² there are low morbidity rates with most operative deliveries.³
It should also be remembered that Caesarean section in the second stage of labour is not without considerable morbidity.
The operator should use their skill and judgement to determine the best choice of instrument for the situation.
The RCOG currently advises that the vacuum extractor should be the first choice.⁴
Although this can have a higher failure rate and increased risks of cephalhaematoma, it has been shown to be associated with less maternal trauma.^5,6

The following factors have been shown to be favourable in avoiding assisted delivery:

• Use of a partogram to monitor progress in labour
• Mother labours in an upright or left lateral position⁶
• Avoidance of use of epidural anaesthesia

The following factors can reduce the number of mid-cavity or rotational deliveries:

• Using oxytocin in a nulliparous mother with an epidural
• Delaying active pushing in a nulliparous mother⁷

They are used to shorten the second stage of labour.
Fetal:

• Presumed, (or diagnosed by fetal blood sampling)compromise

• To avoid Valsalva manoeuvre e.g. in cardiac disease Class 3 or 4
• Hypertensive crises.
• Cardiovascular disease, particularly uncorrected malformations
• Myasthenia Gravis
• Spinal cord injury

• Nulliparous women:
  • Lack of progress for 3 hours ( active and passive stage combined), with regional anaesthesia
  • Lack of progress for 2 hours if no regional anaesthesia
• Multiparous women:
  • Lack of progress for 2 hours if regional anaesthesia in place
  • Lack of progress for 1 hour if no regional anaesthesia in place
  • Maternal fatigue/ exhaustion

• Predisposition to fractures in the fetus
• Bleeding tendency or active bleeding in fetus
• Face presentation and vaccuum extractor
• Gestation ≤ 34 weeks⁸

Full discussion and consent should take place with mother/parents. (Acronym=FORCEPS)

• Cervix fully dilated [F]
• Occipito-Anterior position, preferably. OP possible with Keiilands and Vaccuum. [O]
• Membranes ruptured [R]
• Cephalic presentation [C]
• Greater diameter of baby's head has passed pelvic brim [E] engaged
• Mother is receiving adequate pain relief: [P]
  Vacuum extraction or low forceps - minimum of perineal nerve block
  Mid forceps - epidural or pudendal nerve block or general
• Bladder empty [S] sphincter

These are associated with:

• Maternal BMI ≥ 30
• Estimated fetal weight ≥ 4kg
• OP position
• Mid-cavity deliveries

These factors should prompt trial of delivery with preparations to proceed to Caesarean section immediately, if unsuccessful.
The procedure should be abandoned if no descent is seen with 3 pulls.
An incident report should be completed.
Using differing instruments sequentially is not recommended.⁹

• Vacuum-assisted delivery has a lower rate of successful delivery but is less likely to lead to Caesarean section than the use of forceps.
• Vacuum-assisted delivery is also associated with less use of anaesthesia and fewer severe maternal injuries.
• However, use of forceps following failed vacuum extraction can lead to high level of damage to mother.
• Cephalhaematomas and retinal haemorrhages are well recognised sequelae of vacuum extraction but usually have no long term adverse effects.⁴

Adverse symptoms such as urinary and faecal incontinence are common in mothers with both forms of assisted delivery.^5,6

Suitable subjects may include:

• Rate of use
• Rate of failures
• Incidence of maternal tears
• Neonatal trauma
• Standard of documentation