Childbirth: Coincidence or Cause for Obesity?

It’s one of those deeply entrenched beliefs. Having a baby can be a trigger for weight gain that’s seemingly impossible to shed. But it begs a question. Does having children increase the risk of obesity for a woman? A new study published in Obesity this week suggests that the answer is no.

No Association Between Overweight and Having Children

Deborah Davis and colleagues studied 16 years of data from 8,009 young Australian women. They examined the relationship between parity – having children – and BMI in this cohort from the Australian Longitudinal Study on Women’s Health. Over 16 years, their BMI went up by about four units. But having children did not explain the risk of gaining excess weight or obesity after 16 years of follow up.

What did explain it? The passing of time, depression, lacking a university degree, unemployment, and less physical activity. Each of those variables contributed to the likelihood of developing a BMI above 25. Having babies did not.

Absence of Proof Is Not Proof of Absence

Now, limitations are important to bear in mind. This is not a study of short-term weight gain. Weight gain is part of a healthy pregnancy, of course. These investigators analyzed the change in BMI from the beginning of the study to 16 years later. No doubt, plenty of fluctuation happened in between.

Also, you can be sure that plenty of women in this cohort gained weight when they had children and found that they just couldn’t lose it. But the thing was that women who did not have children had weight gain triggered by other factors. And in the end, it was a bit of a wash.

In no way does this prove that having children can’t be a trigger for overweight or obesity. But an abundance of other potential triggers means that having children doesn’t rise to the top of the list.

When all is said and done, it’s biological susceptibility that sets a person up. You don’t choose it, you inherit it. And then life events and a person’s environment provide triggers. Some people in the same circumstances might be resistant. It’s not a matter of choice.

The only choice in all of this is what you choose to do about it. And those are very personal choices.

Click here for the study, here for a personal reflection on losing baby weight, and here for a reflection on Duchess Kate after giving birth this week.

Mother Roulin with Her Baby, painting by Vincent van Gogh / WikiArt

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April 26, 2018