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Your teeth are pregnant too

Dental health during pregnancy is more important than you might think.

Pregnant women are inundated with advice and dictums from the moment they get the double-blue line: exercise, but get plenty of rest; don’t gain too much weight, but don’t lose any either; take folate and fish oil, but not vitamin A; eat healthily, but not sushi or hummus. Yet one of the risk factors for poor birth outcomes – low birth weight and preterm labour – is all but ignored, and that’s the dental health of the pregnant woman.

There’s a bit of a “disconnect” between the medical community of doctors and midwives who look after pregnant women and the periodontal community, says Michael Danesh-Meyer, a periodontist and director of the Dental Education Continuum. As a result, antenatal care rarely considers dental problems – despite evidence that poor oral health can result in an underweight or premature baby.

The research into this link suggests the risk of these poor birth outcomes could be as much as seven times higher for women with periodontal disease, a chronic infection of the gums and bone supporting the teeth.

Up to a third of the adult population is thought to have periodontal disease, which is a major cause of tooth loss. It’s caused by plaque build-up, which releases bacteria that in turn attack the gums. No one’s immune to getting plaque, and other risk factors include smoking, tooth grinding, some medications such as the Pill and antidepressants, poor nutrition and certain diseases such as diabetes.

At its worst, periodontal disease can cause so much damage to the gum and underlying supporting bone that otherwise healthy teeth have to be removed. And left untreated, it can develop into septicaemia, which is potentially fatal. Although the mechanism behind the link between periodontal disease and preterm labour or low birth weight isn’t well understood, Danesh-Meyer says, the ­studies are well designed and controlled for confounding factors such as smoking and recreational drug use.

However, the link between chronic infection generally and poor birth outcomes is more well known: “If you have a chronic infection – and that’s what periodontal disease is – there is a high probability that bacteria will enter the bloodstream, cross the placenta and affect the baby.”

The studies have been enough for the American Academy of Periodontology (AAP) to recommend that all pregnant women get a clean bill of health. Good advice, of course, for those who can afford it. New Zealand’s poor general dental record is no secret. Multiple studies have found, unsurprisingly, that Kiwis in low socio-economic groups are likely to receive little to no dental care, and the Dunedin Longitudinal Study found solid links between parents reporting their own poor oral health and similarly poor oral health in their children.

And periodontal disease is another issue entirely, as many will not realise they have it because it’s generally asymptomatic. Moreover, Danesh-Meyer says, “if you have an underlying periodontal infection and then become pregnant, that condition will get a lot worse during pregnancy”. Although periodontal disease is a risk factor for poor birth outcomes, pregnancy itself is a risk factor for periodontal disease, as hormonal changes play havoc with teeth and gums.

In short: it’s common, you probably don’t know you have it, pregnancy makes it worse and it, in turn, could affect your child’s health at birth. Citing this research, Labour has pledged free dental care for pregnant women, as has Jim Anderton, and the Green Party supports a free annual check-up for everyone. But although Danesh-Meyer welcomes this interest, he says in an ideal world women would get checked and treated, if need be, before conceiving, as pregnancy complicates treatment options, limiting the painkillers and anaesthetic that can be administered, particularly in the first trimester.

Despite the lack of symptoms, Danesh-Meyer says there are signs of periodontal disease one can look for: swollen or bleeding gums, persistent bad breath, loose teeth or tender gums could all indicate an underlying problem. Not having had a check-up within the past 12 months can allow the condition to worsen unnoticed, as periodontal disease is typically painless until it gets severe. And he adds one other thing to think about: periodontal disease, like heart disease, has a genetic link. If, as an adult, you’re predisposed to it, any offspring you have are likely to be affected, too. So add a commitment to preserving your oral health to your pre-baby checklist. Take folate, don’t drink – and get yourself a thorough dental work-up.


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