Research has linked early menstruation with an increased risk of depression in adolescence.
Conducted by the University of Bristol and the University of Cambridge, the report looked at over 2,000 girls in a long-term study and examined the link between the timing of their first period and the incidence of depressive symptoms.
The mean age at which the study group began menstruating was 12 years and six months.
Those who began their periods before this 11 years and six months had the highest rates of depressive symptoms at the ages of 13 and 14.
Meanwhile, girls who started their periods after 13 years and six months had the lowest levels.
Lead researcher Dr Carol Joinson commented: "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."