eli5: how come only some babies get fetal alcohol syndrome from mother’s alcohol consumption during pregnancy?

Question

also how come some heavy drinking mothers give birth to perfectly healthy babies?

In: 24

Answer 1

Very few things are as simple as “This happened, and here is the consequence,” especially in health. Instead, think of it as going to a roulette wheel at a casino. Unlike the roulette wheel, this wheel has fewer numbers on it. Also, unlike a roulette wheel, you don’t want it to land on your number. So maybe Russian roulette? I don’t own any 5 year olds and so I don’t know if this example goes over their head.

Anyways, the more a mother drinks, the more opportunities for that ball to land on her number, or the bullet lands in her head. Some mothers spin many times. Some mothers spin only a few times. Some mothers walk away (or get by) without ever getting unlucky. But every spin is dangerous.