Maternal dental health has been shown to correlate with premature labor and low birth weight. There are significant hormonal changes during pregnancy which apparently affect the bacteria in the lining of the gums. Gum disease allows oral bacteria to move from the oral cavity into the bloodstream. These oral bacteria may contribute to abnormal and excessive clotting and becomes a risk factor in miniature little clots (emboli) which can travel throughout the bloodstream and deposit in the placenta, or even in the heart or the brain causing complications such as stroke. The oral bacteria may end up depositing on the heart valves or on the inner lining of the heart or pericardium, which is a potentially lethal condition known as endocarditis or pericarditis.
It is now shown beyond any doubt that maternal gum disease causes premature labour. One study performed prospectively in North Carolina looked at the effect of dental health in 812 women. Each woman's dental health was assessed at 26 weeks and then within 48 hours after delivery. The researchers examined both the rate of premature births (less than 28 weeks) and low birth weight (less than 1,000 gms). Their data was adjusted for race, parity and gender. 1.1% of the group with healthy gums (201 women) had premature births. This rate greatly increased to 3.5% in the 566 rated as having mild gum disease and was 11.1% in the 45 women with moderate to severe gum disease. The rates were slightly more dramatic for birth weight. No women with healthy gums had a baby that weighed less than 1,000 gm. Six per cent of the women with mild disease had a baby with low birth weight and 11.4% of those with moderate to severe disease had a low birth weight baby. Studies from Poland, France and Brazil showed similar results. This research applies equally to second trimester and later miscarriages as well as prematurity at term.
The great news is that early attention to periodontal (gum) health can reduce these risks. A study from Chile examined the oral health of 400 pregnant women, aged between 18 and 35, before 28 weeks gestation. Dentists immediately treated periodontal disease in 200 of the women. They treated the other 200 (the controls) only after delivery. The rate of pre-term, low birth weight delivery was 1.8% (3/163) in the treated group and 10.1% (19/188) in the untreated group. Low birth weight and prematurity was 5.5 times more likely in the untreated group.
Prematurity and low birth weight together greatly increase the risk of infant mortality. There are also a large number of other important problems that occur as a result of prematurity. It has taken a long time to recognise this easily preventable cause of preterm labor and low birth weights.
Let us hope that health care professionals and dentists everywhere will work together to provide good prenatal dental care for all pregnant women.
