The new season of Horizon continues to provide lots of food for thought. This week’s episode, “The Nine Months That Made You”, looks at how the environment in the womb may affect the future lives of babies.
If you think about it, it is fairly obvious. We undergo far more “development” before we are born than afterwards. If we, as children and adults, are sensitive to diet and chemicals in the environment, how much more sensitive must we be as foetuses? It is certainly worth investigating.
The bulk of the program revolved around the idea that our susceptibility to things like heart disease and diabetes is a function of the quality of nutrition we get in the womb, as well as of diet and lifestyle after we are born. The statistical evidence presented seemed fairly convincing, and the doctors in India who worked on the project were convinced enough to launch a large-scale and long-term experiment in Mumbai to try to improve the health of the poor by improving the diet of young women.
This isn’t a simple process. It is not just a question of making sure that pregnant mothers get enough to eat. The levels of micro-nutrients such as vitamins are apparently crucial. Also it is a multi-generational project. Some of the factors involved may depend on whether certain genes are switched on in the mother’s eggs and, as women are born with a fully stocked ovaries, your ability to bear a healthy child may be in part dependent on the quality of diet your mother had when she was bearing you.
What interested me most, however, was when they went beyond health issues and started to look at personality. There was a nice experiment in which they showed that foetuses have clear personalities (something that most mothers know, but doctors need to prove), so the sort of person we become is not entirely down to our environment and upbringing.
Another experiment related the level of testosterone in the womb to the type of gendered behaviour shown by the resulting children. Girls exposed to higher levels of testosterone are apparently more likely to exhibit gendered behaviour that is generally associated with boys. I’m pretty sceptical of such experiments because they are often carried out by people with a poor understanding of gender, and with lots of cultural bias, but it does hold out the possibility of starting to understand the origins of transsexuality.
Talking of gender differences, I saw a report yesterday that purported to explain why women are much less fond of horror movies than men. Apparently women get much more stressed by the clues that something bad is about to happen. Again I am sceptical of such things. There may be a lot of cultural training and expectation involved here. All I can say is that I’m very female-typical here and always have been. My mum had to take me out of The Wizard of Oz when I first saw it because I found it too scary.
Of course I also view such things as a science fiction reader. If we can build better babies, how far will people take this? How much human variation do we want to “cure”? Whereas the treatments being given to poor women in Mumbai are cheap and simple, what procedures will be developed that only the rich can afford? Science, as always, is a double-edged sword.