University of Warwick researchers found that most very preterm and very low birthweight (VP/VLBW) infants were securely attached to their parents.

But they also found that VP/VLBW infants were at higher risk for what is termed 'disorganised attachment' -- when a child shows conflicting behaviour in their relationship with their parents.

Healthy attachment sees a child using the parent as a secure base from which to explore the world, whereas with disorganised attachment the child displays contradictory behaviour when interacting with the parent.

Disorganised attachment can be an indicator of negative parenting and abuse in full-term infants, so the study underlines the need for health professionals to know whether a child was born prematurely when assessing parent-baby relationships.

The study -- Very preterm/very low birthweight infants' attachment: infant and maternal characteristics -- was led by Professor Dieter Wolke at the University of Warwick and published in the journal Archives of Disease in Childhood: Fetal and Neonatal Edition.

Professor Wolke said: "Very preterm children often spend months in incubators and in hospital after birth. Despite this stressful start we found parents of very preterm children to be as sensitive in their parenting as those of healthy preterm children. However, very preterm children more often have neurological and developmental problems and these explained why they were more likely to be disorganised in their attachment or bonding despite sensitive parenting. "

Professor Wolke added: "Health professionals should be aware that disorganised attachment in preterm children is often a sign of these children's developmental problems and not because they are harshly or abusively parented."

The study looked at 71 VP/VLBW children and 105 full-term children. It defined very preterm as babies born at less than 32 weeks gestation or weighing less than 1500g (3lb 5 oz).

The study found that most very preterm/very low birthweight (VPV/LB) infants (61 per cent) were securely attached to their primary caregiver. That compares to 72 per cent of full-term children.

However 32 per cent of VP/VLBW children showed disorganised attachment at 18 months, compared with 17 per cent of full-term children.

The researchers also studied maternal sensitivity in the way mothers interacted with their babies.

They found that the differences in attachment emerged despite mothers of VP/VLBW children being equally or more sensitive in their parenting in comparison with mothers of full-term infants.

This suggests that disorganised attachment is linked to neurological abnormalities, and not to maternal sensitivity.

However parents of VP/VLBW children should take heart from separate research which showed a more positive impact of parenting at a later age.

For example, a study last year, also led by University of Warwick academics, found that sensitive parenting did help older VP/VLBW children -- aged between six and eight years old -- to make up developmental delays.