Methods

Allocation by "random selection". Method not specified.

Participants

Inclusion criteria: singleton frank breech presentation; 36 weeks or more gestation; estimated fetal weight between 2500 and 3800 g; cervical dilation 7 cm or less. Exclusion criteria: hyperextension of the fetal head or evidence of fetal skeletal anomalies on abdominal x‐ray; elderly primigravidae; obstetric indication for caesarean section; class B‐F diabetes mellitus; floating station; involuntary infertility; pelvic contracture by previous x‐ray pelvimetry; history of previous difficult or traumatic delivery. 208 women randomised to vaginal delivery group (115 women) and caesarean section group (93 women).

Interventions

Planned delivery by caesarean section compared with a policy of vaginal breech delivery; x‐ray pelvimetry was performed and if 1 or more pelvic inlet or mid‐cavity measurements were reduced, caesarean section performed; oxytocin induction was permitted only for premature rupture of membranes with the fetus engaged in the maternal pelvis; oxytocin augmentation of labour was used for prolonged latent phase and protracted active phase dilation; fetal heart rate and uterine contractions were monitored throughout labour. Delivery by or supervised by a senior obstetric resident.

Outcomes

Actual use of caesarean section; brachial plexus injury; Apgar score < 7 at 5 minutes; short‐term neonatal morbidity; perinatal mortality; maternal morbidity.

Notes

Los Angeles, California, USA. Data presented for 4 groups according to protocol selection and actual method of delivery. For this review, analysed according to protocol selection only (i.e. according to 'intention‐to‐treat'). A large discrepancy in numbers between groups (93 versus 115, and 37 versus 57 multiparous women) is not accounted for.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

High risk

Allocation by "random selection". Method not specified. Reason for large discrepancy in group sizes not given. High risk of selection bias.

Allocation concealment (selection bias)

High risk

Inadequate.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Not possible due to the nature of the intervention. No attempt at partial blinding described.

Blinding of outcome assessment (detection bias)
All outcomes

High risk

No blinding described.

Incomplete outcome data (attrition bias)
All outcomes

Unclear risk

No incomplete data. Difference in group sizes not explained.

Selective reporting (reporting bias)

Unclear risk

Insufficient evidence to assess whether all prespecified outcomes were reported.

Other bias

Unclear risk

Insuficient detail in reporting to be sure whether additional risk exists.

Methods

2‐arm trial. "Randomisation" in a ratio of 1 caesarean section to 2 trials of labour, to allow for exclusions from trial of labour. Method of randomisation not specified.

Participants

Inclusion criteria: singleton pregnancy; non‐frank breech presentation on abdominal x‐ray; in labour; estimated gestational age 36‐42 weeks; estimated fetal weight 2000 to 4000 g; cervix < 7 cm dilated; non‐extended normal appearing fetal skull on x‐ray; no contraindication to labour. Of 105 enrolled, 35 allocated to caesarean section and 70 to trial of labour.
Exclusion criteria: severe pregnancy‐induced hypertension; more than 1 prior caesarean section; previous stillbirth; history of infertility; class B diabetes mellitus; impaired intrauterine growth; abnormal antepartum fetal heart rate testing; abnormal amniotic fluid volume; multiple gestation. 105 women were randomised to trial of labour (70 women) or elective caesarean section (35 women).

Interventions

Planned elective caesarean section compared with planned trial of labour: x‐ray pelvimetry performed and trial of labour allowed if measurements were at least 11 cm at anteroposterior diameter of the inlet, 12 cm at widest transverse diameter of the inlet and 10 cm between ischial spines at the midpelvis; continuous electronic fetal monitoring; oxytocin infusion on an optional basis for poor progress of labour; intravenous analgesia and assisted breech delivery with application of Piper forceps to aftercoming head. Delivery supervised by chief resident and/or obstetric staff.

Outcomes

Actual use of caesarean section; brachial plexus injury; Apgar score < 7 at 5 minutes; perinatal mortality; maternal morbidity.

Notes

Los Angeles. California, USA. Results reported in the study in 4 groups according to allocated and actual method of delivery. For this review analysed according to allocated method of delivery ('intention‐to‐treat') only.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Unclear risk

Not specified, stated only as "randomisation" done. High risk of selection bias.

Allocation concealment (selection bias)

Unclear risk

Not described.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Not possible due to the nature of the intervention. No attempt at partial blinding described.

Blinding of outcome assessment (detection bias)
All outcomes

High risk

No blinding described.

Incomplete outcome data (attrition bias)
All outcomes

Unclear risk

3 women appear to have been excluded shortly after randomisation: 2 progressed so rapidly to emergency caesarean section that x‐rays could not be obtained, and the third had inadequate pelvic dimensions so elected caesarean section.

Selective reporting (reporting bias)

Unclear risk

Insufficient evidence to assess whether all prespecified outcomes were reported.

Other bias

Unclear risk

Report not detailed enough to be sure of other bias

Methods

Centrally controlled computerised randomisation, stratified by parity (0 or > 0) and block sizes of 2.

Participants

Inclusion criteria: singleton live fetus; frank or complete breech presentation; 37 or more weeks' gestation.
Exclusion criteria: fetopelvic disproportion; fetus judged to be 'large', or estimated 4000 g or more; hyperextension of fetal head; fetal anomaly or mechanical problem likely to affect delivery; contraindication to labour or vaginal delivery; known lethal fetal anomaly. 2088 women were randomly assigned to planned vaginal delivery (1045 women) or planned caesarean section (1043 women)

Interventions

Planned caesarean section: if not in labour, scheduled for 38 or more weeks' gestation if known, or following maturity testing or onset of labour. If no longer breech presentation, method of delivery reviewed.
Planned vaginal birth: await spontaneous labour; induction or augmentation allowed if indicated; caesarean section if indication arose, including fetal heart rate abnormality or inadequate labour progress; assisted breech delivery by an experienced clinician; total breech extraction avoided.

Outcomes

Primary: perinatal or neonatal mortality up to 28 days of age (excluding lethal congenital abnormalities) or specified serious neonatal morbidity.
Secondary: maternal mortality or specified serious maternal morbidity.
3‐month follow‐up: breastfeeding; infant health; ease of caring for infant; ease of adjusting to being a mother; sexual relations; relationship with partner; pain; urinary, flatus and faecal incontinence; depression; views regarding childbirth experience and participation in study, 2‐year follow‐up in selected centres: perinatal/infant death or neurodevelopmental delay at age 2 years; maternal health at 2 years; economic aspects (costs) of interventions.

Notes

Multicentre trial. Countries classified as having low (20/1000 or less) or high perinatal mortality rates. Follow‐up at 3 months excluding centres unable to accomplish 80% follow‐up.

Risk of bias

Bias

Authors' judgement

Support for judgement

Random sequence generation (selection bias)

Low risk

Centrally controlled computerised randomisation.

Allocation concealment (selection bias)

Low risk

Adequate, random allocation accessed by means of a touch‐tone telephone.

Blinding of participants and personnel (performance bias)
All outcomes

High risk

Not possible due to the nature of the intervention. No attempt at partial blinding described.

Blinding of outcome assessment (detection bias)
All outcomes

Unclear risk

Blinding was not possible for most outcomes. Group allocation was masked for the assessment of a few outcomes (e.g. diagnosis of severe morbidity was made by the steering committee masked to the group allocation (Hannah 2000 p1377) and diagnosis of neonatal outcomes such as lethal congenital abnormality and Down syndrome were also masked to group allocation (Whyte 2004 p865)).

Incomplete outcome data (attrition bias)
All outcomes

Low risk

No unbalanced loss to follow‐up ‐ only 2 + 3 lost to follow‐up from 2088 women.

Selective reporting (reporting bias)

Low risk

All outcomes measured appear to have been reported

Other bias

Unclear risk

Baseline characteristics similar. Analysis by intention‐to‐treat. Study was stopped early because of significant differences in perinatal or neonatal mortality at less than 28 days of age (excluding lethal congenial anomalies). Some protocol violations may have biased the results towards favouring caesarean section (e.g. including the recruitment of babies who may already have been dead, twin pregnancies, not having an experienced clinician at vaginal breech deliveries, and including babies with footling or "uncertain" breech presentation). 58 out of 646 women who had vaginal deliveries violated the protocol (Lawson 2012).