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Abstract

Routine use of a partograph is associated with a reduction in the use of forceps, but is not associated with a reduction in the use of vacuum extraction (Level A). Early artificial rupture of the membranes, associated with oxytocin perfusion, does not reduce the number of operative vaginal deliveries (Level A), but does increase the rate of fetal heart rate abnormalities (Level B). Early correction of lack of progress in dilatation by oxytocin perfusion can reduce the number of operative vaginal deliveries (Level B). The use of low-concentration epidural infusions of bupivacaine potentiated by morphinomimetics reduces the number of operative interventions compared with larger doses (Level A). Placement of an epidural before 3-cm dilatation does not increase the number of operative vaginal deliveries (Level A).

Posterior positions of the fetus result in more operative vaginal deliveries (Level B). Manual rotation of the fetus from a posterior position to an anterior position may reduce the number of operative deliveries (Level C). Walking during labour is not associated with a reduction in the number of operative vaginal deliveries (Level A). Continuous support of the parturient by a midwife or partner/family member during labour reduces the number of operative vaginal deliveries (Level A). Under epidural analgesia, delayed pushing (2 h after full dilatation) reduces the number of difficult operative vaginal deliveries (Level A). Ultrasound is recommended if there is any clinical doubt about the presentation of the fetus (Level B).

The available scientific data are insufficient to contra-indicate attempted midoperative delivery (professional consensus). The duration of the operative intervention is slightly shorter with forceps than with a vacuum extractor (Level C). Nonetheless, the urgency of operative delivery is not a reason to choose one instrument over another (professional consensus). The cup-shaped vacuum extractor seems to be the instrument of choice for operative deliveries of fetuses in a cephalic transverse position, and may also be preferred for fetuses in a posterior position (professional consensus). Vacuum extraction deliveries fail more often than forceps deliveries (Level B).

Overall, immediate maternal complications are more common for forceps deliveries than vacuum extraction deliveries (Level B). Compared with forceps, operative vaginal delivery using a vacuum extractor appears to reduce the number of episiotomies (Level B), first- and second-degree perineal lesions, and damage to the anal sphincter (Level B). Among the long-term complications, the rate of urinary incontinence is similar following forceps, vacuum extraction and spontaneous vaginal deliveries (Level B). Anal incontinence is more common following forceps delivery (Level B). Persistent anal incontinence has a similar prevalence regardless of the mode of delivery (caesarean or vaginal, instrumental or non-instrumental), suggesting the involvement of other factors (Level B). Rates of immediate neonatal mortality and morbidity are similar for forceps and vacuum extraction deliveries (Level B). It appears that difficult instrumental delivery may lead to psychological sequelae that may result in a decision not to have more children (Level C). The rates of neonatal convulsions, intracranial haemorrhage and jaundice do not differ between forceps and vacuum extraction deliveries (Levels B and C).

Rapid sequence induction with a Sellick manoeuvre (pressure to the cricoid cartilage) and tracheal intubation with a balloon catheter is recommended for any general anaesthesia (Level B).

Training must ensure that obstetricians can identify indications and contra-indications, choose the appropriate instrument, use the instruments correctly, and know the principles of quality control applied to operative vaginal delivery. Nowadays, traditional training can be accompanied by simulations. Training should be individualized and extended for some students.

Keywords: Instrumental delivery, Guidelines, Forceps, Vacuum extractor, Spatulas.

 

1. Introduction and method [1] and [2]
The French College of Gynaecologists and Obstetricians appointed an organization committee (Appendix A) for the development of these guidelines. This committee was tasked with defining the exact questions to ask the expert authors, to choose these experts, follow them up, and draft the synthesis of recommendations resulting from their work. The expert authors analysed the scientific literature on the subject in order to answer the questions raised. A literature search of MEDLINE and the Cochrane Library was conducted to locate relevant literature up to mid-2008. The search was restricted to articles published in English and French. Priority was given to articles reporting the results of original research, although review articles and commentaries were also consulted. Guidelines published by organizations or institutions, such as the Royal College of Obstetricians and Gynaecologists, the American College of Obstetricians and Gynaecologists, and the Society of Obstetricians and Gynaecologists of Canada, were reviewed, and additional studies were located by reviewing the bibliographies of identified articles.

For each question, an overview of the validated scientific data was assigned a level of evidence according to the quality of the data available, using the working framework defined by the French Health Authority.

1.1. Quality of evidence assessment
•• LE1: very powerful randomized comparative trials, meta-analysis of randomized comparative trials.
•• LE2: not very powerful randomized trials, well-run non-randomized comparative studies, cohort studies.
•• LE3: case–control studies.
•• LE4: non-randomized comparative studies with large biases, retrospective studies, transversal studies, case series.
A synthesis of recommendations was drafted by the organizing committee based on the replies given by the expert authors. Each recommendation for practice was classified in accordance with the levels defined by the French Health Authority.

1.2. Classification of recommendations
•• Level A: recommendations are based on good and consistent scientific evidence.
•• Level B: recommendations are based on limited or inconsistent scientific evidence.
•• Level C: recommendations are based primarily on consensus and expert opinion.
•• Professional consensus: in the absence of any conclusive scientific evidence, some practices are recommended on the basis of agreement between the members of the working group.
All articles were reviewed by individuals who were not involved in the work, i.e. practitioners in the specialties concerned (Appendix A), working in various public, private, university or non-university establishments. Once the articles had been reviewed, changes were made, if necessary, considering assessment of the quality evidence. The individual references included in each article [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], and [13] are not reported in this paper due to space constraints.

 
2. Measures during labour to reduce the number of operative vaginal deliveries [3]
2.1. During the first phase of labour
Routine use of a partograph is associated with a reduction in the use of forceps, but is not associated with a reduction in the use of vacuum extraction (Level A). The improvement occurs because interventions are more relevant for the correction of anomalies.

Early artificial rupture of the membranes, associated with oxytocin perfusion, does not reduce the number of operative vaginal deliveries (Level A), but does increase the rate of fetal heart rate (FHR) abnormalities (Level B). Early correction of lack of progress in dilatation by oxytocin perfusion can reduce the number of operative vaginal deliveries (Level B).

Regional analgesia with doses of local anaesthesia >0.125 increases the rate of operative vaginal deliveries (Level A). The use of very low doses potentiated by morphinomimetics reduces the number of operative interventions compared with larger doses (Level A). Placement of an epidural before 3-cm dilatation does not increase the number of operative vaginal deliveries (Level A).

Posterior positions of the fetus result in more operative vaginal deliveries (Level B). Manual rotation of the fetus from a posterior position to an anterior position may reduce the number of operative deliveries (Level C).

Walking during labour is not associated with a reduction in the number of operative vaginal deliveries (Level A). Continuous support of the parturient by a midwife or partner/family member during labour reduces the number of operative vaginal deliveries (Level A).

2.2. During the second phase of labour
Use of a partograph promotes objective interpretation of the situation and assessment of the risk of instrument use (Level B).

A standing, squatting or lateral position during the second phase of labour is not associated with a significant reduction in the number of operative vaginal deliveries compared with a dorsal decubitus or supine position (Level B).

Under epidural analgesia, delayed pushing (2 h after full dilatation) reduces the number of difficult operative vaginal deliveries (Level A). Fundal pressure manoeuvres do not reduce the number of operative vaginal deliveries (Level B).

 
3. Indications and prerequisites for operative vaginal deliveries: when? who? how? where? [4]
3.1. Necessary preconditions for instrument use
The necessary preconditions for instrument use include: thorough knowledge of the medical and obstetric file (professional consensus), ruptured membranes, cephalic presentation, full dilatation (Level C), and engagement of the head (professional consensus). Ultrasound is recommended if there is any clinical doubt about the presentation of the fetus (Level B). Appropriate maternal analgesia, rigorous asepsis (professional consensus) and an empty bladder (professional consensus) are also needed. The intervention must be explained to the patient before commencement (professional consensus).

The choice of instrument depends on the obstetric situation and the obstetrician's preference (professional consensus). The need to perform an episiotomy depends on the judgement of the operator (professional consensus).

An operative vaginal delivery must be performed in conditions such that, if it fails, a rapid caesarean section is possible.

The obstetrician should perform the operative delivery in the presence of a midwife and, if possible, a third person (professional consensus). The presence of an anaesthetist is not mandatory, but is desirable in case of insufficient maternal analgesia. The presence of an anaesthetist is recommended in at-risk situations (professional consensus). Similarly, although the presence of a pediatrician is not essential, the obstetrician may request that a pediatrician be called or be informed that his/her presence may be required imminently (professional consensus).

3.2. Indications
The principal indications for instrument use are FHR abnormalities which suggest that fetal acidosis is occurring or impending (Level C).

Instrumental delivery should be envisioned after 30 min of pushing with normal FHR, when the intensity of contractions is judged to be sufficient but the fetus fails to descend (professional consensus). Operative delivery is also recommended if the patient has any contra-indications to the Valsalva manoeuvre (professional consensus).

3.3. Relative contra-indications
The available scientific data are insufficient to contra-indicate attempted midoperative delivery (professional consensus).

 
4. Forceps [5]
Forceps are used in operative deliveries to guide the descending fetus. Placement and traction differ with the type of forceps. The use of crossed-blade forceps for a fetus in a transverse position is contra-indicated (professional consensus), and convergent-blade forceps or, ideally, another instrument (spatula or vacuum extraction) should be used (professional consensus). Operative vaginal delivery with forceps should be abandoned when fetal descent fails to progress after three contractions (Level C).

 
5. Vacuum extraction [6]
A vacuum extractor allows cephalic flexion, traction and induction of rotation. The effectiveness of operative delivery by vacuum extraction is highly dependent on the equipment used and compliance with the manufacturer's instructions.

For fetuses in transverse, posterior and sacro-occipital positions, intrapelvic rotation generally induces the occiput forward with vacuum extraction, provided that the cup is placed correctly (Level C).

A vacuum extractor should not be used for more than 20 min (professional consensus). After three pulls, the extraction must be deemed to have failed and must be abandoned (professional consensus).

 
6. Spatulas [7]
Spatulas are instruments of propulsion and direction; their mechanism of action and handling are fundamentally different to those of forceps. Spatulas are difficult to handle for fetuses in posterior positions and mid-station, and require specific training. There is no evidence for or against rotational manoeuvres using spatulas. A preliminary attempt at manual rotation may be advised.

The use of spatulas appears to be atraumatic for the fetus (professional consensus). However, episiotomy is more common when spatulas are used, although this observation is often based on routine practice which is a matter of debate (professional consensus).

 
7. Comparison between vacuum extraction and forceps deliveries [8]
The duration of the operative intervention is slightly shorter with forceps than with a vacuum extractor (Level C). Nonetheless, the urgency of operative delivery is not a reason to choose one instrument over another (professional consensus).

The cup-shaped vacuum extractor seems to be the instrument of choice for operative delivery of fetuses in a cephalic transverse position, and may also be preferred for fetuses in a posterior position (professional consensus).

Vacuum extraction deliveries fail more often than forceps deliveries (Level B). Sequential application of these interventions is highly controversial. The failure of a forceps delivery should lead to a caesarean section (professional consensus). No evidence justifies a preference for forceps or caesarean delivery after the failure of vacuum extraction. The decision must be made on a case-by-case basis based on the operator's experience (professional consensus).

7.1. Maternal complications
Overall, immediate maternal complications are more common for forceps deliveries than vacuum extraction deliveries (Level B). Compared with forceps, operative vaginal delivery using a vacuum extractor appears to reduce the number of episiotomies (Level B), first- and second-degree perineal lesions, and damage to the anal sphincter (Level B).

Among the long-term complications, the rate of urinary incontinence is simular following forceps, vacuum extraction and spontaneous vaginal deliveries (Level B). Anal incontinence is more common after forceps delivery (Level B).

7.2. Neonatal complications
The rates of immediate neonatal mortality and morbidity are similar for forceps and vacuum extraction deliveries (Level B). The rates of neonatal convulsions, intracranial haemorrhage and jaundice do not differ between forceps and vacuum extraction deliveries (Levels B and C).

 
8. Obstetric anaesthesia for operative vaginal deliveries
When choosing the site and type of anaesthesia, consideration must be given to the potential risk of caesarean section, estimated for each case, and local organizational constraints (professional consensus). Regardless of the technique chosen, the standard safety rules of the French Society of Anaesthesiologists must be followed.

When effective epidural analgesia is in place, it may be insufficient for labour, especially for forceps use. It is therefore necessary to notify the anaesthesia team so they can decide if it should be re-inforced.

Rapid sequence induction with a Sellick manoeuvre (pressure to the cricoid cartilage) and tracheal intubation with a balloon catheter is recommended for any general anaesthesia (Level B).

Greater post-intervention and post-anaesthesia surveillance is needed following operative vaginal delivery compared with spontaneous delivery. This should last for at least 2 h.

 
9. Maternal complications of operative vaginal deliveries
9.1. Immediate and short-term complications
The risk of severe perineal lacerations (third and fourth degree) is significantly greater for operative vaginal deliveries compared with spontaneous vaginal deliveries (Level B). Numerous factors are involved in the risk of severe perineal lesions, including: application to a higher station, especially if associated with rotation >45° (Level B); posterior position of the fetus (Level B); and fetal macrosomia.

The 2006 French clinical guidelines on episiotomy did not conclude that routine episiotomy had any advantages. Nonetheless, a mediolateral episiotomy may reduce the risk of sphincter lacerations with both vacuum extraction and forceps deliveries (Level C). This must be determined on a case-by-case basis.

Sequential use of two instruments indicates a difficult delivery, and multiplies the risks compared with spontaneous vaginal delivery or operative vaginal delivery using a single instrument (Level C).

9.2. Late and long-term complications
Instrumental delivery, especially forceps delivery, appears to be associated with increased risk of anal incontinence over the following year (Level B). The risk of occult anal sphincter lesions does not appear to differ between forceps and vacuum extraction deliveries (Level B). Persistent anal incontinence has a similar prevalence regardless of the mode of delivery (caesarean or vaginal, instrumental or non-instrumental), suggesting the involvement of other factors (Level B).

Instrumental delivery does not seem to be associated with increased risk of persistent post-partum urinary incontinence compared with spontaneous vaginal delivery (Level B), and instrumental delivery does not appear to promote pelvic organ prolapse (Level C). Instrumental delivery and the presence of severe perineal lacerations increase the risk of perineal pain, dyspareunia and post-partum sexual disorders compared with spontaneous vaginal delivery (Level C).

It appears that difficult instrumental delivery may cause psychological sequelae that may result in a decision not to have more children (Level C).

 
10. Neonatal complications of operative vaginal deliveries
In addition to the complications associated with instrumental delivery in the strict sense, more severe, benign (usually) complications can occur that may involve the technique, but may occur instead or in addition to the events that led to operative intervention, such as dystocia or fetal anoxia. These complications are also observed in normal deliveries.

10.1. Complications associated with vacuum extraction
Cephalhaematomas, diffuse subcutaneous haematomas of the scalp (subgaleal haematoma) and retinal haemorrhages are more common with vacuum extraction deliveries (Level B). The risk of (much rarer) intracranial haemorrhage is increased for vacuum extraction deliveries (Level C). All these types of haemorrhage have a good short-term prognosis, except for diffuse subcutaneous haematoma which is very rare. The frequency of haemorrhage may be underestimated.

10.2. Complications of operative vaginal delivery using forceps
The rare risk of a depressed skull fracture is fairly specific to the use of forceps (Level B). It is generally asymptomatic.

10.3. Long-term complications
The use of instruments does not seem to induce neurocognitive sequelae (Level B).

 
11. Training for operative vaginal deliveries
Training must ensure that obstetricians can identify indications and contra-indications, choose the appropriate instrument, use the instruments correctly, and know the principles of quality control applied to operative vaginal delivery.

The training programme must include simultaneous training in the use of forceps, vacuum extractors and, if possible, spatulas (complementarity of instruments). Excellent knowledge of the mechanics of obstetrics is required.

Nowadays, traditional training can be accompanied by simulations. The use of simulations in training also helps to resolve the problem that extensive experience in a large number of procedures is desirable but difficult to attain in real life. Training should be individualized and extended for some students.

The danger of instrumental deliveries depends more on the operator's skill than on the instrument itself. The assessment of training should consider both teachers and trainees. Sessions should be held to evaluate department-wide professional practices and should cover quality criteria associated with operative vaginal deliveries. The involvement of obstetricians may improve practices (Hawthorne effect).

 
Conflict of interest
None declared.

 
Appendix A. Appendix A
A.1. Steering committee
J.F. OURY, President (gynaecologist/obstetrician, Hôpital Robert-Debré, Paris, France), C. VAYSSIERE, Coordinator and Methodologist (gynaecologist/obstetrician, CHU Toulouse, Toulouse, France), A. FOURNIE (gynaecologist/obstetrician, CHU Angers, Angers, France), F. GALLEY-RAULIN (midwife, CH Verdun, Verdun, France),

A.2. Working group
O. BAUD (neonatologist, Hôpital Robert-Debré, Paris France), G. BEUCHER (gynaecologist/obstetrician, CHU Caen, Caen, France), P. DIEMUNSCH (anesthesiologist, CHU Hautepierre, Strasbourg, France), O. DUPUIS (gynaecologist/obstetrician, CHU Lyon-Sud, Lyon, France), O. FERAUD (gynaecologist/obstetrician, Hôpital Robert-Debré, Paris, France), E. MEUNIER (midwife, Maternité Port-Royal, CHU Cochin, Paris, France), O. PARANT (gynaecologist/obstetrician, CHU Toulouse, Toulouse, France), D. RIETHMULLER (gynaecologist/obstetrician, CHU Besançon, Besançon, France), J.P. SCHAAL (gynaecologist/obstetrician, CHU Grenoble, Grnoble, France), T. SCHMITZ (gynaecologist/obstetrician, Maternité Port-Royal, CHU Cochin, Paris, France), L. SENTILHES (gynaecologist/obstetrician, CHU Angers, Angers, France), C. SIMON-TOULZA (gynaecologist/obstetrician, CHU Toulouse, Toulouse, France).

A.3. Peer reviewers
F. ANDRES (midwife, CHU Toulouse, Toulouse, France), A. BARBIER (gynaecologist/obstetrician, CHU Nancy, Nancy, France), J. BERTHET (gynaecologist/obstetrician, CH du Lamentin, France), G. BOOG (gynaecologist/obstetrician, CHU Nantes, Nantes, France), B. CARBONNE (gynaecologist/obstetrician, CHU Saint-Antoine, Paris, France), T. DEBILLON (pediatrician, CHU Grenoble, Grenoble, France), M. DREYFUS (gynaecologist/obstetrician, CHU Caen, Caen, France), C. EBOUE (gynaecologist/obstetrician, CHU Caen, Caen, France), S. FAVRIN (gynaecologist/obstetrician, Clinique de l’Union, Toulouse, France), P. GILLARD (gynaecologist/obstetrician, CHU Angers, Angers, France), F. GOFFINET (gynaecologist/obstetrician, Maternité Port-Royal, CHU Cochin, Paris, France), V. GRANDIN (midwife, CHG Lons-le-Saunier, Lons-le-Saunier, France), P. HOFFMANN (gynaecologist/obstetrician, CHU Grenoble, Grenoble, France), R. KUTNAHORSKY (gynaecologist/obstetrician, CH Colmar, Colmar, France), V. LEJEUNE (gynaecologist/obstetrician, CHG Auch, Auch, France), C. Le Ray (gynaecologist/obstetrician, Montreal, Queberc, Canada), G. MAGNIN (gynaecologist/obstetrician, CHU Poitiers, Poitiers, France), P. MAHIOU (anesthesiologist, Clinique Echirolles, France), R. MAILLET (gynaecologist/obstetrician, CHU Besançon, Besançon, France), L. MARPEAU (gynaecologist/obstetrician, CHU Rouen, Rouen, France), F. MENJOZ (midwife, CH Chambery, Chambery, France), X. MORIN (gynaecologist/obstetrician, Clinique Echirolles, France), F. N’GUYEN (midwife, CHI Poissy, Poissy, France), R.C. RUDIGOZ (gynaecologist/obstetrician, CHU Hôpital de la Croix Rousse, Lyon, France), C. SEGUIN (midwife, Montbonnot, France), F. TEURNIER (midwife, CNSF, Fontenay-sous-bois, France), M. ZANARDI-BRAILLON (midwife, CHU Reims, Reims, France), V. ZUPAN (pediatrician, CHU Antoine Beclere, Clamart, France).

 
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Footnotes
a Service de Gynécologie-Obstétrique, Hôpital Paule de Viguier, CHU Toulouse, Toulouse, France

b UMR 1027, Inserm Université Toulouse III, ‘Epidémiologie Périnatale et handicap de l’enfant, Santé des adolescents’, Toulouse, France

c Service de Gynécologie-Obstétrique, CHU Caen, Caen, France

d Service de Gynécologie-Obstétrique, CHU Lyon, Lyon, France

e Service de Gynécologie-Obstétrique, Hôpital de Robert-Debré, Paris, France

f Service de Gynécologie-Obstétrique, CHU Angers, Angers, France

g Service de Gynécologie-Obstétrique, Maternité Port-Royal, CHU Cochin, Paris, France

h Service de Gynécologie-Obstétrique, CHU Besançon, Besançon, France

i Service de Pédiatrie, Hôpital Robert-Debré, Paris, France

j Service de Gynécologie-Obstétrique, Centre hospitalier de Verdun, Verdun, France

k Service d’Anesthesie-Réanimation, CHU d’Hautepierre, Strasbourg, France

l Service de Gynécologie-Obstétrique, CHU Poitier, Poitiers, France

m Service de Gynécologie-Obstétrique, CHU Grenoble, Grenoble, France

 Corresponding author at: Hôpital Paule de Viguier, CHU Toulouse, 330 av de Grande Bretagne, 31059 Toulouse, France. Tel.: +33 567771216; fax: +33 567771219.