A new study shows that waiting at least 3 minutes before cutting a baby's umbilical cord could speed up their development later in life.
In the study, a psychologist assessed the children using tests of IQ, motor skills and behaviour.
The researchers found that overall, there was no difference in brain development and behaviour scores for babies whose cord were clamped early or late.
There was no difference in overall IQ scores between the two groups of children either.
But more children in the delayed cord clamping group had a mature pencil grip on the fine motor skills test.
They also had better skills on some social domains, compared to those whose cords were clamped early.
Divided by sex, the researchers only found noticeable differences in boys, not in girls.
Iron deficiency is much more common among male infants than among females, Dr Andersson said.
'Girls have higher iron stores when they are born,' he said.
Delaying cord clamping by three minutes allows an extra 3.5 ounces of blood to transfuse to the baby, which is equivalent to a half a gallon of blood for an adult, he added.
'There's a lot of iron in that volume,' he said.
'Even three minutes can have quite a lot of effect on the iron in the blood in the body for a long time after birth.'
The World Health Organisation recommends waiting at least one minute after birth, or until visible pulsing stops, to clamp the umbilical cord.
