Guidelines on foetus size ‘will change obstetrics’

New guidelines which will help doctors distinguish between foetuses with a potentially fatal growth restriction and “normally small” babies will “change obstetrics completely”, according to the chair of the group behind the research.

The guidelines, which are to be published today, were developed following an Irish study by the Perinatal Ireland Network, funded by the Health Research Board, involving 1,100 foetuses in the bottom 10 per cent weight bracket.

Previously all foetuses in this cohort were considered at risk, affecting about 7,000 pregnancies a year in Ireland. However, some 70 per cent of those pregnancies resulted in babies who did not have foetal growth restriction.

Stillbirth
Foetal growth restriction can result in stillbirth or a higher chance of cerebral palsy, bleeding in the brain and, in cases where the birth is induced early, prematurity and associated complications.

Prof Fergal Malone, chairman of Perinatal Ireland, consultant obstetrician and gynaecologist at the Rotunda hospital and RCSI professor of obstetrics and gynaecology, said distinguishing between “normally small” foetuses and at-risk babies was a common and complex problem in maternity care.

Distinction
"We have always struggled to discover which of that 10 per cent were 'normally small' and which are 'abnormally small'." He added that this was the "first time internationally" that researchers had been able to make this distinction.

The research, led by RCSI fellow in maternal foetal medicine Dr Julia Untersheider, found that foetuses in the bottom 3 per cent weight bracket had a "much, much higher chance" of being abnormally small.

The other major finding was that other foetuses in the bottom 10 per cent weight category required special monitoring if they showed an abnormal reading on a particular ultrasound, a Doppler scan of the umbilical artery.