On the plus side, it tastes like death! A study on a bunch of 8-year-olds in Finland, where licorice is basically one of the food groups, found that the children whose mothers had consumed more than 100 grams of pure licorice during pregnancy performed worse than their peers on a variety of cognitive functions, including vocabulary, memory and spatial awareness. They were also more likely to be diagnosed with ADHD.
But hey, at least they didn't have to eat any.
The culprit appears to be a component in the candy called glycyrrhizin, which, in addition to harboring a severe vowel deficiency, may impair the placenta and allow more stress hormones to pass from the mother to the fetus. This kind of makes the baby stressed by proxy, so the fetus starts producing a hormone called cortisol to deal with it.
This leads to the children having levels of cortisol
up to one-third higher than their peers have. Cortisol increases your tolerance of stress, so it's beneficial if you want to be, say, a brain surgeon or a professional lion castrator. Unfortunately, too much of it is also linked to diabetes, obesity, high blood pressure and all sorts of brain problems. Finally, we have somebody else to blame for our failing education system: the Finns.