Girls who go through puberty early are more likely to suffer mental health problems in their teenage years because of arguments with parents and boyfriend troubles, a study has found.
Evidence suggests girls are now going through puberty earlier than before - with improved nutrition and high levels of pollution suggested as possible causes.
Now research conducted by University of Bristol and the University of Cambridge has found a link between when a girl first menstruated and symptoms of depression.
The findings published in the British Journal of Psychiatry found that girls who started their periods before the age of 11.5 years had the highest rates of depression at 13 and 14.
By comparison, girls who started their periods after the age of 13.5 had the lowest rates of depression.
Lead researcher Dr Carol Joinson said: "Our study found that girls who mature early are more vulnerable to developing depressive symptoms by the time they reach their mid-teens. This suggests that later maturation may be protective against psychological distress. Early maturing girls may feel isolated, and faced with demands which they are not emotionally prepared for."