We're realising now that the development of the brain is sensitive to the hormones that are around it, and particularly cortisol, just as it is to alcohol, smoking or other drugs. And that the cortisol level that the fetus experiences will set a number of brain receptors to cortisol and this in turn will set later responses. It's very important that we learn to understand what's the optimal development here because it's much easier to change things while they're being made than to try and change them later. If, for example, it turns out that high levels of maternal stress—or even different methods of delivery, really have adverse affects on the development of the baby's brain, it's important to understand more about this and address it at this period, than have children with behavioral problems more difficult to resolve later.