Pregnant women carrying boys need more energy

Average energy intake among pregnant women carrying a boy compared with a girl BMJ Volume 326, pp 1245-6

Researchers analysed the dietary intake of 244 pregnant women attending a large hospital in Boston, United States.

They found that women who were carrying a male embryo had an 8% higher intake of protein, a 9% higher intake of carbohydrates, an 11% higher intake of animal fats, and a 15% higher intake of vegetable fats than women who were carrying a female embryo.

These findings support the theory that women carrying male rather than female embryos may have higher energy requirements and that male embryos may be more susceptible to a low energy intake, say the authors.

They suggest that the signal from the fetus responsible for the higher energy intake of women carrying a boy could be related to the strongly anabolic testosterone secreted by the fetal testicles, but other alternatives deserve scientific investigation.