Just had a look at this on iPlayer and it's a very good program. I remember looking at some of the older studies mentioned when I was studying at university so lots of very good quality research went into the factors that they mention.
The effects on nutrition in pregnancy is one of the factors that is thought to be responsible for differences in health of different European countries. For example, the French eat as much fat and drink as much alcohol as many other countries in Europe but have much lower rates of heart disease and diabetes. This may seem puzzling until you find out that during the second world war pregnant women in France were entitled to extra rations, a policy that was apparently unusual in Europe at the time...
Fascinating stuff!