Table 3.

Definitions of “emergency transfer” across the studies

Study	Study definitions of emergency transfers
Amelink-Verburg et al.[24]	“…a referral for a complication that cannot be treated at the primary care level and that requires immediate diagnostics or treatment at the secondary care level” (Mother: Fetal distress, placental problems, abnormal presentation together with ruptured membranes, postpartum haemorrhage > 1000 ml, intrapartum fetal death. Neonate: early postnatal Apgar score >7 at 5 minutes, respiratory problems including meconium aspiration, congenital malformations with need of immediate care).
Anderson et al.[22]	Failure to progress, fetal distress, meconium in liquor, nonvertex presentations, postpartum haemorrhage, neonatal asphyxia, serious anomalies.
Blix et al.[25]	That the condition of the mother, fetus or infant demanded medical assistance as soon as possible.
Davies et al.[23]	Need for obstetric intervention within one hour after transfer.
Janssen et al.[19]	Fetal distress, meconium in liquor, breech presentation, active herpes, midwife not available, obstructed labour, retained placenta, repair episiotomy, postpartum haemorrhage, asphyxia, neonatal respiratory distress, distended abdomen in infant.
Johnson and Daviss [4]	Based on primary reason for transport.
Hansen et al.[27]	Poor fetal heart rate.
Hutton et al.[18]	Transported from home to hospital by ambulance during labour or immediately after delivery.