Children are great. But too much of a good thing could cause your wife to lose her teeth, a new study in the British Medical Journal suggests. The research lends weight to the old wives’ tale “gain a child, lose a tooth” and makes a strong case for childbirth being a long-term nightmare. Specifically, the researchers found that mothers of more than two kids of the same sex are more likely to suffer tooth loss than others.
“Our study provides unique and novel evidence for causal links between the number of natural children and missing teeth,” according to the study. But dad’s teeth remained firmly in gums, no matter the number of kids. “An additional birth might be detrimental to the mother’s but not the father’s oral health.”
The purported link between having kids and gumming your pudding is not exactly new. Nearly 20 percent of women believed they would lose a tooth after each pregnancy, according to one study. Other research looked at the medical records of 1,821 women and 1,057 men and found that the more children women had, the more dental problems they experienced. While tooth loss is also linked to lower socioeconomic status, and women who have more kids tend to be more socially disadvantaged, a large study out of Yale controlled for socioeconomic status and found that the correlation between fertility and losing teeth held.
In this new study, researchers demonstrated that having a third child significantly increased a mother’s risk of losing her teeth, but only if the two previous children were of the same sex. They found that women, on average, lose 0.57 teeth per child and have 0.88 fewer teeth if children are of the same sex.
A key limitation of the research is that is was only meant to establish a correlation between the number of children and missing teeth, so it cannot demonstrate that having children causes tooth loss. It could have something to do with the fact that hormonal changes during pregnancy can cause gingivitis to develop in about half of women, and such persistent inflammation could cause teeth to fall out. Or perhaps it’s due to a combination of factors, not the least of which is the poor self-care associated with parenthood. It’s not even clear that modern dads are immune to baby-induced tooth loss, because the dataset was representative of an older generation of fathers who may have been less engaged with their kids.
“The changing roles of modern-day fathers might provide an interesting analytical setup: if causal research would detect no relevant effects for fathers which are younger than those observed in our study, this might provide evidence against parenting-related impacts on oral health,” researchers conclude. “Further research is needed to establish refined interventions against tooth loss.”
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