Methods	Randomised trial; method not stated.
Participants	Inclusion: established preterm labour in cephalic presentation between 26-33 weeks; single pregnancy; no contraindication to caesarean or vaginal delivery; no congenital anomalies. Setting (period of recruitment): Los Angeles County/University of Southern California Medical Center (1981). Number of randomised participants: elective 23, selective 15
Interventions	I: vaginal delivery vs II: caesarean delivery.
Outcomes	Major maternal postpartum complications Birth injury to infant Birth asphyxia I: 2/9, II: 1/5 Mode of birth Neonatal death I: 1/9, II: 1/5 Neonatal admission to NICU Postpartum haemorrhage Hypoxic ischaemic encephalopathy I: 2/9, II: 1/5 Breastfeeding at discharge Breastfeeding at 3 months Cord pH below normal range Abnormal follow-up in childhood Neonatal fitting Meconium aspiration Apgar score at 5 min Maternal satisfaction
Notes	Trial terminated after 6 months because the proportion (63%) of babies with birthweight > 1500 g was “unacceptably high”
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Details of random sequence generation not reported.
Allocation concealment (selection bias)	Unclear risk	Details of allocation concealment not reported.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not blinded.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information reported for definitive evaluation of outcome assessment
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	2 women excluded for malpresentation after randomisation. Vaginal delivery group includes 3 randomised to caesarean section who delivered vaginally prior to surgery.
Selective reporting (reporting bias)	Unclear risk	Data for 14 cases eligible for the < 1500 g group reported separately
Other bias	Unclear risk	High frequency of infants with weight > 1500 g. 38 women participated in total of which only 14 were eligible for the <1500 g group. After enrolling 40 women study discontinued. Trialists had planned to enrol 175 in each group