If you’re born via C-section, you’re more likely to grow up overweight, have allergies, and have asthma. But here's a catch: you have to be a mouse.
When babies are born, they have gut microbes, and some of these microbes are from the mother’s vaginal canal. But C-section babies don’t have these microbes, and their ecosystem of microbes or microbiomes look different. And that comes with different health issues like allergies, asthma, and growing up overweight later in life.
Researcher Maria Dominguez-Bello and her colleagues wanted to find out if C-section really leads to the latter. So they compared 35 vaginally born mice with 34 C-section ones. After 15 weeks, when these mice have grown into adults, the C-section mice were a third heavier than those vaginally born. And females are the most affected, where they are 70 percent heavier than vaginally born mice, compared to males which were 20 percent heavier than vaginally born mice. “We were very surprised to see this,” Dominguez-Bello says. “We have no idea why it’s happening.”
But they don’t actually have higher body fat, instead, their tissues, bones and fat just grow much more. Not only that, the C-section mice’s microbiomes are less diverse than their vaginally-born counterparts. However, it’s not clear whether those C-section mice are unhealthy. Nonetheless, based from this, the researchers theorized that lack of vaginal bacteria could lead to obesity in humans later in life.
But Phillip Bennett of Imperial College London disagrees. While mice have an extremely diverse set of vaginal bacteria, humans’ vaginal bacteria are dominated largely by a single strain. “You’re 1.3 times more likely to be obese if you’re delivered by Caesarean section than vaginally,” Bennett says. But this is largely because obese mothers are more likely to bear children via C-section and women pregnant with larger offspring. Bennett added that at any rate, C-section births don’t vastly increase the risk of obesity in human offspring.
So, mothers in general, you need not to worry too much until further studies. Here's to giving birth and, of course, making babies! (Wink.)
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