An early onset of puberty can increase the risk of behavioural problems in girls, new research shows.comedy_nose/Flickr

An early onset of puberty can increase the risk of behavioural problems in girls, new research shows.

Menarche, the landmark sign of puberty in girls, normally starts after a girl turns 11 years old. However, recent research has highlighted a sudden change in the occurrence and has shown that these days children enter puberty at an early age, compared to earlier generations.

In the new study, published in the online issue of Pediatrics, researchers linked early puberty to delinquency and physical aggression in teen girls. Though the aggressive nature disappeared as the girls aged, delinquency and negative peer influences remained.

The study observed 2,607 girls. They self-reported the age they hit puberty, their behaviour and nature of their friends. Researchers interviewed parents at different stages of growth at the ages 11, 13 and 16. 

Results showed that early puberty made teenage girls misbehave. The authors concluded that "early-maturing girls are at risk of persistently higher delinquency and stronger negative peer influences."

Though the link between early puberty and behavioural problems was clear, researchers urged parents not to panic as many other factors can also contribute to the occurrence. "There could also be other reasons, such as family structure and socioeconomic status, that may drive both early puberty and problem behaviors," lead researcher Sylvie Mrug, of the University of Alabama at Birmingham, told Health Day. 

Mrug also said people often evaluate these children by their physical development. "These girls look older and are treated by others as older, but they may not have the social and [thinking] skills to deal with these external pressures," Mrug added.

Accoridng to health experts at the Mayo Clinic in US, many factors contributed to the early onset of puberty in children. Obesity, medical conditions like Albright syndrome, congenital adrenal hyperplasia or hypothyroidism, or coming into direct contact with hormones oestrogen or testosterone are some of them. Early puberty has many severe side-effects, such as stunted growth in children and low self-esteem. Studies have shown that an early menarche placed women at the risk of cardiovascular disease, metabolic dysfunction and cancer later in life.