Girls who are overweight often enter puberty earlier than girls who have a normal weight, Germany's professional association for gynaecologists reported, citing a study sponsored by the University of Michigan.

The Munich-based organization said girls who have been overweight since the age of 3 often experience breast development and other signs of puberty as young as 9. Breasts normally begin to develop after age 10.

The US scientists observed developments in body weight and body mass index in 350 girls through age 12. The body mass index is calculated by dividing body weight in kg by height in m sq.

(Agencies via China Daily December 14, 2007)