Pregnant women who regularly see the dentist and hygienist may reduce their risk of a premature birth by a third, a new research has suggested.

Researchers from the Harvard School of Dental Medicine found that women with gum disease who were at high risk of having a premature birth benefited from having a procedure called scaling and root planing.

Having a scale and polish removes the build-up of tartar from near the gumline, in turn reducing the risk of severe gum disease, they said.

Doctors have previously established that severe gum infections cause an increase in the production of prostaglandin and tumour necrosis factor, chemicals which induce labour, to be produced.

The new research, published in the Journal of Periodontology, found there was a 34 per cent reduction in the risk of preterm births for expectant mothers suffering with gum disease if they underwent simple treatment at the dentist or hygienist.

Dr Nigel Carter, Chief Executive of the British Dental Health Foundation, said the research affirmed the need for expectant mothers to take care of their oral health during pregnancy.

He added that the importance of regular appointments with the dentist and hygienist could not be underestimated.