Natural childbirth, breastfeeding and survivorship bias

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“We’re still here!”

It’s a favorite declaration of those attempting to justify natural parenting practices:

Childbirth without interventions must be optimal because we’re still here.

Homebirth must be safe because we’re still here.

Exclusive breastfeeding must be best because we’re still here.

[pullquote align=”right” cite=”” link=”” color=”” class=”” size=””]Looking at those today alive today though their parents never used seatbelts, we might conclude that seatbelts are unnecessary because “we’re still here.”[/pullquote]

But “we’re still here” doesn’t merely fail to justify natural parenting practices, it is actually a form of cognitive bias, a way of thinking that inevitably leads us to erroneous conclusions.

Specifically, “we’re still here” is a form of survivorship bias, a bias so subtle that it is often difficult for its practitioners to recognize.

Rational Wiki defines survivorship bias as:

… a cognitive bias that occurs when someone tries to make a decision based on past successes, while ignoring past failures.

Rational Wiki offers an excellent example of survivorship bias:

Suppose you’re trying to help the military decide how best to armor their planes for future bombing runs. They let you look over the planes that made it back, and you note that some areas get shot heavily, while other areas hardly get shot at all. So, you should increase the armor on the areas that get shot, right?

Wrong! These are the planes that got shot and survived. It stands to reason that on some planes, the areas where you don’t see any damage did get shot, and they didn’t survive. So those are the areas you reinforce…

Dead men (and planes) may tell no tales, but the fact that they are dead provides valuable information for the survivors.

The planes that returned from the bombing runs aren’t the safest planes; they’re the ones that were merely lucky enough to get hit in the places least likely to cause catastrophic damage.

For example, imagine that every plane that returned was shot somewhere in the fuselage, but never in the fuel tank. In contrast, every plane that was shot in the fuel tank failed to survive because a shot to the fuel tank inevitably led to explosion of the entire plane.

If you were to repair the returning planes and send them out on another bombing run a substantial proportion would once again fail to return because this time they might get hit in the fuel tank. Surviving the first bombing run because they were not shot in the fuel tank would not have made them more likely to avoid getting shot in the fuel tank the second time.

In other words, the pilots who survived the first bombing run were simply luckier than the ones who failed to return.

Consider a more common example.

Most of us above a certain age traveled in cars throughout our entire childhoods without ever using a seatbelt and we’re still here. For many years cars didn’t even have seatbelts yet the population of the US continued to increase. Does that mean seatbelts are useless?

Of course not! The many children who died from being ejected in car accidents are testament to the fact that failure to wear a seatbelt is dangerous. The dramatically lower death rates for children in accidents in the 2010’s compared to the 1960’s makes it clear that wearing a seatbelt is much safer than not wearing one. But if we only looked at people alive today even though their parents never used seatbelts, survivorship bias would lead us to conclude that seatbelts are unnecessary.

Dead children leave no descendants; their millions of potential descendants are not here but we don’t notice precisely because they are absent. We are the remainder.

How does this apply to natural parenting?

The claim that childbirth without interventions is safe because “we are still here” makes as much sense as claiming that not wearing seatbelts in the 1960’s was safe because “we are still here.”

The claim that homebirth is safe because for most of human existence women gave birth at home and “we are still here” makes as much sense as claiming that putting babies to sleep on their stomachs instead of their backs is safe because “we are still here.”

The claim that breastmilk must be better than formula because “we are still here” is like claiming riding without a bicycle helmet must be better than using a helmet because “we are still here.”

But billions of potential people are NOT here today precisely because their parents died in childbirth, at homebirth, or from being exclusively breastfed by women who didn’t produce enough milk for them to survive.

We who are “still here” are the remainder, representing nothing more than luck, not inherent safety.