Assisted Vaginal Birth

• Classification

• Indications

• Contraindications

• Assessment

• Precautions

• Complications

• Midwifery Responsibilities

• Documentation

• Post Birth Management

• References

Purpose

Definition

Classification of Types of Assisted Vaginal Birth

Indications for Assisted Vaginal Birth

• non-reassuring fetal status on CTG / scalp lactate measurement
• abruptio placenta in second stage
• cord prolapse in second stage (multigravida)
• 'any condition that makes it unsafe for the fetus to remain in the uterus during second stage' (ALSO)

• Medical indications to avoid strong pushing (Valsalva technique) e.g. severe cardiac disease, hypertensive disorders, cerebral vascular disease/ uncorrected cerebral vascular malformations, myasthenia gravis, spinal cord injury.
• Inadequate progress: (Approximate intervals for a prolonged second stage):

• Maternal fatigue/ exhaustion

Contraindications

Relative Contraindications

• Fetal bleeding disorders (alloimmune thrombocytopenia, haemophilia, von Willebrand's disease - in these circumstances vacuum extraction should not be performed - non-rotational low or outlet forceps may be permissible after consultant discussion).
• Risk of vertical transmission of Hepatitis C and HIV: Avoidance of acquired infection as a result of an increased chance of facial or scalp abrasions.

Contraindications

• Fetal predisposition to fractures (e.g. osteogenesis imperfecta)
• Face presentation - forceps only to be used
• Prematurity of <34 weeks gestation - forceps only to be used

Assessment prior to Assisted Vaginal Birth

Precautions prior to undertaking assisted delivery

• In primigravidas, the use of oxytocin (to augment labour) should be considered for managing delay in the second stage of labour before the fetal head reaches the pelvic floor, rather than initiating early instrumental intervention. The use of oxytocin at this stage in women who have previously had a baby has the potential to cause uterine rupture.
  
  

• Assisted vaginal births with an anticipated higher rate of failure should be considered a trial and conducted in the operating theatre.

• A consultant obstetrician should be present for all attempts at mid-cavity or rotational forceps, and all "trials of forceps".
• The need for instrumental birth is associated with the potential for shoulder dystocia. Refer to the Women's CPG: Shoulder Dystocia.
  

• The need for mediolateral episiotomy should be considered.
• Paediatrician to be present for the delivery where neonatal morbidity can be reasonably anticipated, including but not limited to all cases of suspected fetal compromise, mid-cavity and rotational deliveries.

• Attempted vaginal delivery should be abandoned where:

Potential and Relative Complications of Assisted Vaginal Birth

Midwifery Responsibilities

• Reassurance of woman, support person(s)
• Continual monitoring and documentation of fetal status
• Timing of contractions manually. Informing operator of onset prior to traction being applied and cessation of same to enable any manipulation of equipment.
• Observation/ documentation of time of application of instrument and how many contractions required for birth of baby
• Ensure Paediatrician is informed of event/ Check neonatal resuscitation equipment
• Midwifery care & documentation according to the Women's procedure: Observations of Labouring Women (intranet only) and Midwifery Standards: Birth Suites pamphlet.
  
  

Documentation of Procedure

• Indication for intervention
• A record of discussion with the woman of the risks, benefits of the procedure and her options
• Description of fetal CTG and contractions
• Abdominal palpation: position of fetus & station of fetal head
• Consultation with senior medical officer

• The findings of vaginal examinations including:

• The duration of traction and force required
• A description of maternal and neonatal injuries and their management
• Record of the paired umbilical cord gases (venous and arterial)

Post Birth Management

• Repair of perineal trauma: refer to the Women's CPGs:

• Bladder management: Urinary output should be monitored for at least 24 hours post birth to detect postpartum urinary retention. A post-void residual urine should be measured if retention is suspected.
  For a woman who has experienced an assisted birth/ prolonged labour/ epidural anaesthesia, consider an indwelling urinary catheter for twelve hours following the birth to prevent asymptomatic bladder overfilling. Refer to the Women's CPG: Peripartum Bladder Management. Women should be offered physiotherapy-directed strategies to prevent urinary incontinence.
  
  

• Analgesia: If there are no contraindications provide diclofenac and paracetamol at regularly prescribed intervals. Icepacks can be applied to the perineum at regular intervals for up to 48 hours.
  
  

• Thromboprophylaxis: Assess woman in relation to individual risk factors.
  
  

• Observe neonate for signs of jaundice, infection and any concerns about tissue or nerve related injury.
  
  

• The accoucheur and primary midwife should review the woman prior to hospital discharge and discuss the indication for operative delivery, management of any complications and the prognosis for future deliveries.

References