In addition to these evidence-based recommendations, the guideline development group also identifies points of best clinical practice in the original guideline document.
Classification of evidence levels (1++ to 4) and grades of recommendations (A-D) are defined at the end of the "Major Recommendations" field.
Preparation for Operative Vaginal Delivery
Can Operative Vaginal Delivery Be Avoided?
A - All women should be encouraged to have continuous support during labour as this can reduce the need for operative vaginal delivery.
A - Use of upright or lateral positions and avoiding epidural analgesia can reduce the need for operative vaginal delivery.
A - Delayed pushing in primiparous women with an epidural can reduce the need for rotational and midcavity deliveries.
How Should Operative Vaginal Delivery Be Classified?
D - A standard classification of operative vaginal delivery should be used.
When Should Operative Vaginal Delivery Be Offered?
B - Operators should be aware that no indication is absolute and should be able to distinguish 'standard' from 'special' indications.
D - A vacuum extractor should not be used at gestations of less than 34 weeks +0 days. The safety of vacuum extraction at between 34 weeks +0 days and 36 weeks +0 days of gestation is uncertain and should therefore be used with caution.
Operative intervention is used to shorten the second stage of labour. It may be indicated for conditions of the fetus or of the mother (see Table 2 in the original guideline document). The benefits of a shortened second stage for certain medical conditions should be discussed where possible in the antenatal period. The time constraints listed in Table 2 in the original guideline document are for guidance. The question of when to intervene should involve balancing the risks and benefits of continuing pushing versus an operative delivery. [Evidence level 2-]
What Are the Essential Conditions for Safe Operative Vaginal Delivery?
D - Safe operative vaginal delivery requires a careful assessment of the clinical situation, clear communication with the mother and healthcare personnel and expertise in the chosen procedure.
The table below lists prerequisites for operative vaginal delivery. Like any operative intervention, adequate preparation and planning is important. Be cautious in the urgent situation and at handover periods when time pressures can limit the information given.
Table: Prerequisites for Operative Vaginal Delivery
|Full Abdominal and Vaginal Examination
||Head is ≤1/5th palpable per abdomen
Cervix is fully dilated and the membranes ruptured.
Exact position of the head can be determined so proper placement of the instrument can be achieved.
Assessment of caput and moulding
Pelvis is deemed adequate. Irreducible moulding may indicate cephalo-pelvic disproportion.
|Preparation of Mother
||Clear explanation should be given and informed consent obtained.
Appropriate analgesia is in place for mid-cavity rotational deliveries. This will usually be a regional block. A pudendal block may be appropriate, particularly in the context of urgent delivery.
Maternal bladder has been emptied recently. In-dwelling catheter should be removed or balloon deflated.
|Preparation of Staff
||Operator must have the knowledge, experience and skill necessary.
Adequate facilities are available (appropriate equipment, bed, lighting).
Back-up plan in place in case of failure to deliver. When conducting mid-cavity deliveries, theatre staff should be immediately available to allow a caesarean section to be performed without delay (less than 30 minutes). A senior obstetrician competent in performing mid-cavity deliveries should be present if a junior trainee is performing the delivery.
Anticipation of complications that may arise (e.g., shoulder dystocia, postpartum haemorrhage)
Personnel present that are trained in neonatal resuscitation
Performing Operative Vaginal Delivery
Who Should Perform Operative Vaginal Delivery?
D - An operative vaginal delivery should be performed by an operator who has the knowledge, experience and skills necessary to assess and to use the instruments and manage complications that may arise.
Where Should Operative Vaginal Delivery Take Place?
C - Operative vaginal births that have a higher risk of failure should be considered a trial and conducted in a place where immediate recourse to caesarean section can be undertaken.
Higher rates of failure are associated with:
- Maternal body mass index over 30
- Estimated fetal weight over 4000 g or clinically big baby
- Occipito-posterior position
- Mid-cavity delivery or when 1/5th of the head palpable per abdomen.
The risks of failed operative vaginal delivery in the labour room should be balanced with the risks associated with the transfer time when the delivery is conducted in an operating theatre. [Evidence levels 2- to 4]
What Instruments Should Be Used for Operative Vaginal Delivery?
A - The operator should choose the instrument most appropriate to the clinical circumstances and their level of skill. Forceps and vacuum extraction are associated with different benefits and risks. Failed delivery with selected instrument is more likely with vacuum extraction.
When Should Operative Vaginal Delivery Be Abandoned?
B - Operative vaginal delivery should be abandoned where there is no evidence of progressive descent with moderate traction during each contraction or where delivery is not imminent following three contractions of a correctly applied instrument by an experienced operator.
Is There a Place for Sequential Use of Instruments?
B - The use of sequential instruments is associated with an increased risk of trauma to the infant; however, the operator must balance the risks of a caesarean section following failed vacuum extraction with the risks of forceps delivery following failed vacuum extraction.
What Is the Role of Episiotomy for Operative Vaginal Delivery?
B - In the absence of robust evidence to support routine use of episiotomy in operative vaginal delivery, restrictive use of episiotomy, using the operator's individual judgement, is supported.
Should Prophylactic Antibiotics Be Given?
A - There are insufficient data to justify the use of prophylactic antibiotics in operative vaginal delivery
Aftercare Following Operative Vaginal Delivery
Should Thromboprophylaxis Be Given?
D - Women should be reassessed after an operative vaginal delivery for risk factors for venous thromboembolism and, if appropriate, thromboprophylaxis should be prescribed.
What Precautions Should Be Taken for Care of the Bladder after Delivery?
C - The timing and volume of the first void urine should be monitored and documented.
A - Women should be offered physiotherapy-directed strategies to prevent urinary incontinence.
Urine retention with bladder overdistension should be avoided, particularly in women who have had spinal or dense epidural blocks. At a minimum the first void should be measured, and if retention is a possibility a post-void residual should be measured to ensure that retention does not go unrecognised. [Evidence level 2+]
How Can We Reduce Psychological Morbidity for the Mother?
A - There is no evidence to support the use of midwife-led debriefing in reducing maternal depression following operative vaginal delivery.
How Should We Advise Women for Future Deliveries?
B - Women should be encouraged to aim for a spontaneous vaginal delivery in a subsequent pregnancy as there is a high probability of success.
Grades of Recommendations
A - At least one meta-analysis, systematic review or randomised controlled trial rated as 1++ and directly applicable to the target population; or
A systematic review of randomised controlled trials or a body of evidence consisting principally of studies rated as 1+ directly applicable to the target population and demonstrating overall consistency of results
B - A body of evidence including studies rated as 2++ directly applicable to the target population, and demonstrating overall consistency of results; or
Extrapolated evidence from studies rated as 1++ or 1+
C - A body of evidence including studies rated as 2+ directly applicable to the target population and demonstrating overall consistency of results; or
Extrapolated evidence from studies rated as 2++
D - Evidence level 3 or 4; or
Extrapolated evidence from studies rated as 2+
Good Practice Point - Recommended best practice based on the clinical experience of the guideline development group
Classification of Evidence Levels
1++ High-quality meta-analyses, systematic reviews of randomised controlled trials or randomised controlled trials with a very low risk of bias
1+ Well-conducted meta-analyses, systematic reviews of randomised controlled trials, or randomised controlled trials with a low risk of bias
1– Meta-analyses, systematic reviews of randomised controlled trials or randomised controlled trials with a high risk of bias
2++ High-quality systematic reviews of case–control or cohort studies or high-quality case–control or cohort studies with a very low risk of confounding, bias or chance and a high probability that the relationship is causal
2+ Well-conducted case–control or cohort studies with a low risk of confounding, bias or chance and a moderate probability that the relationship is causal
2– Case–control or cohort studies with a high risk of confounding, bias, or chance and a significant risk that the relationship is not causal
3 Non-analytical studies; e.g., case reports, case series
4 Expert opinion