Dr Muiris Houston, Medical Correspondent, describes therisk factors facing premature babies
The death of Jennifer Jane Brown, 11 days after she was born 7 weeks prematurely is a tragedy for the Chancellor of the Exchequer and his wife, Sarah.
Jennifer was born by Caesarean section when doctors became concerned about her growth and development at a routine ante-natal visit. Her birth weight, at 1.1 kgs, was below what would be expected of a baby at 33 weeks gestation.
She initially did well but at the weekend she deteriorated following a brain haemorrhage. Intracranial bleeding is a recognised risk of prematurity.
Although babies routinely survive from 24-26 weeks gestation, the chances of a problem developing in the neonatal period are directly related to the level of prematurity at birth.
Lack of maturity affects the state of blood vessels, the fragility of which are one possible cause of a haemorrhage. Clotting factors in the blood may not have developed to full maturity either, so that once a bleed commences the blood's normal defence mechanisms are unable to function.
The development of low oxygen levels [hypoxia] in the baby's brain while it is still in the womb is an independent risk factor for brain haemorrhage in the newborn.
The fact that Jennifer Brown was in some intrauterine difficulty leading to her early delivery by emergency Caesarean section suggests that hypoxia was a feature in her sustaining an intracranial bleed.
Other known risk factors for brain haemorrhage in the newborn, such as a prolonged labour, or a breech delivery, can be discounted in this case, as Caesarean section was the mode of delivery.
Ever since her deterioration on Saturday it was likely that Jennifer Brown would have some residual disability, had she lived.
Cerebral Palsy is the term used to describe the range of neurological disorders which can result from a severe insult in the perinatal period - such as brain haemorrhage.
The condition affects between 1.5 per cent and 3.5 per cent of all live births.