Artist's depiction of a foetus at 38 weeks' gestation<unk>  or 'brain-sparing' is a diagnosis in<unk>  medicine. It is characterised by preferential flow of blood towards the brain at the expense of the other vital organs, and it occurs as a haemodynamic adaptation in foetuses which have placental insufficiency. The underlying mechanism is thought to be vasodilation of the<unk>  arteries.<unk><unk>  is defined by the presence of a low middle<unk>  artery pulsatility index (MCA-PI). Ultrasound of the middle<unk>  artery to examine the Doppler waveform is used to establish this. Although<unk><unk>  represents an effort to preserve brain development in the face of hypoxic stress, it is nonetheless associated with adverse neurodevelopmental outcome. The presence of<unk><unk>  will be one factor taken into consideration when deciding whether to artificially deliver a baby with placental insufficiency via induction of labour or caesarian section.
Foetal cerebral redistribution
Persistent fetal circulation
Umbilical cord compression
Placental insufficiency
Fetal-maternal haemorrhage
Traumatic asphyxia
Maternal fetal stress transfer
Amniotic fluid embolism