Girls who start puberty very early are more likely to have psychological problems and be at risk of sexual abuse and early pregnancy, suggests a new review published in The Obstetrician & Gynaecologist (TOG).

Puberty is characterised by the maturation of the hypothalamic pituitary gonadal (HPG) axis, which plays a critical part in the development and regulation of the reproductive system.

Normal puberty commences from approximately 10 years onwards and breast development is usually the first sign of this. In Europe, the lower end of the normal range for the onset of puberty is 8 years in girls, although there are ethnic variations.

In girls, early puberty or precocious puberty is defined as the development of secondary sexual characteristics, such as the development of breasts or pubic hair before the age of 8 years. Most children with premature sexual development need referral to a paediatric endocrinologist for evaluation and management.

There are two main types of precocious puberty; the first is central precocious puberty (CPP) which results from premature activation of the HPG axis and in the majority of cases the cause is unknown. The other type is peripheral precocious puberty which results from production of sex hormones and can be caused by ovarian tumours or adrenal disorders.

Girls who start puberty early can be affected both physically and psychologically, says the review. In addition to the early physical signs of puberty, although the child may initially present with tall stature as the bones mature faster, growth may cease early and compromise final adult height.

Due to higher levels of sex steroids normally seen in older girls, psychological problems may arise resulting in adolescent behaviour. In addition, psychological problems can also arise if the child is expected to behave according to their physical maturity rather than their age. The review also states that girls are at increased risk of sexual abuse and early pregnancy.

The review also looks at the treatment for early puberty. Treatment will depend on the type of precocious puberty and the underlying cause, if known. The goal of treatment for precocious puberty is to stop, and possibly reverse the onset of puberty, improve final height and to avoid psychosocial /behavioural effects.

Most children with CPP can be treated effectively with Gonadotrophin-releasing hormone analogues (GnRHa), which control the release of the hormones responsible for the development of secondary sexual characteristics. Possible side effects include headaches, hot flushes, mood swings and rashes.

This treatment is normally stopped when it is time for normal puberty to begin. The decision to discontinue treatment should be taken jointly by the endocrinologist, the child and the parents, says the review.

The review concludes that the decision whether to provide treatment or not is a difficult one, in particular, for girls who commence puberty between 6 and 8 years old.

Sakunthala Sahithi Tirumuru, Specialist Registrar, Department of Obstetrics and Gynaecology, Alexandra Hospital, Redditch, and co-author of the review said:

"Starting puberty early can have a significant impact both psychologically and socially on both the child and her family. Puberty marks the start of a child's sexual development and early onset could result in a higher risk of sexual abuse.

"This all needs to be considered by the healthcare team and further studies are needed to evaluate the effects of hormone treatment on quality of life and long term impact."

TOG's Editor-in-Chief, Jason Waugh said:

"Girls who start puberty earlier than their peers may experience difficulties and treatment may be required. However the long term effects of hormone treatment needs to be explored further."