Maternal vitamin C deficiency during pregnancy can have serious consequences for the fetal brain. And once brain damage has occurred, it cannot be reversed by vitamin C supplements after birth.
... between 10-20 per cent of all adults in the developed world suffer from vitamin C deficiency. Therefore, pregnant women should think twice about omitting the daily vitamin pill.
"Even marginal vitamin C deficiency in the mother stunts the fetal hippocampus, the important memory centre, by 10-15 per cent, preventing the brain from optimal development,"... [emphasis mine]