That maternal diet and baby health are linked would seem right at an intuitive level, but there is increasing evidence that the mechanisms involved are really quite complex. A recent study has shown that a maternal diet low in protein can have the effect of increasing levels of the male hormone, testosterone, in the mothers' placenta and this can result in an increased risk of high blood pressure (hypertension) in the baby in later years. In other words, if your mother was on a low protein diet, you are more likely to suffer from high blood pressure. It is thought that the cause of this is that a low protein diet results in reduced activity of an enzyme that normally inactivates testosterone; this allows more testosterone to reach the baby in the womb and thereby increases the offspring's susceptibility to adulthood hypertension.
The impact of maternal stress on an unborn child's physical characteristics at birth, as well as its long-term health is known as "foetal programming". Due to the role that the placenta plays in hormone production and nutrient transport, it is believed to also play a major role in foetal programming. It has been known that elevated testosterone levels are associated with pregnancy-related complications such as pre-eclampsia and polycystic ovary syndrome, but the new work by a team of scientists at The University of Texas Medical Branch at Galveston, USA suggests that testosterone may also play a role in foetal programming of blood pressure.