Researchers from the Mind, Brain and Behaviour Research Centre (CIMCYC), the Department of Pharmacology (Faculty of Pharmacy), and the Faculty of Psychology have analysed the levels of cortisol (a steroid hormone that is released in response to stress) in the hair of pregnant women in the period spanning from before conception to week 9 of pregnancy, to determine whether there was any link with the sex of the baby.
A total of 108 women were monitored from the first weeks of pregnancy through to delivery, to record their stress levels before, during, and after conception via the concentration of cortisol in their hair and various psychological tests.