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It turns out that girls may not be the only ones who are developing early. According to new research, boys may be entering puberty at a younger age than they were a few decades ago.

A generation ago, 11 or 12 was considered the average age for boys and girls to go through the physiologic changes that accompany puberty. Now, the onset age appears to be shifting younger, with an increasing number of children going through puberty at 9 or 10.

Although the difference is only a year or two, it is a significant change that could have implications for development, behaviour and even long-term health. It also poses complex new challenges to parents, who face having "the talk" earlier than expected, and to children, who will be trying to navigate a confusing time at an earlier stage of their emotional and psychological development.

"I don't think most parents are really prepared for their sons to go into early puberty in Grade 5," said Dr. Dina Panagiotopoulos, a pediatric endocrinologist at B.C. Children's Hospital and a clinician scientist at the Child and Family Research Institute based in Vancouver.

Unlike girls, who develop breasts, the onset of puberty is not as obvious in boys. Panagiotopoulos said parents should be on the lookout for changes in their child's behaviour or mood and talk to them about puberty.

Over the past few years, health experts debated whether the trend was confined to girls. In the 1990s, research emerged showing that girls were entering puberty earlier than they were in previous decades. Although the phenomenon is now widely accepted by the medical community, the discussion continues over the impact that earlier onset of puberty has on childhood development, behaviour and future health of girls. For instance, some research has linked earlier onset of puberty to a higher risk of breast cancer.

Last weekend, the American Academy of Pediatrics published an important new study that provides, for the first time, highly credible scientific evidence that the same is true for boys.

The study, based on U.S. research, found that puberty among boys is starting six months to two years earlier than previously documented. Ethnic trends emerged as well: For white boys, the earliest stage of puberty is occurring at 10.14 years, while among Hispanic boys, the onset is at 10.4 years. Black boys showed the earliest average age of onset, at 9.14 years. Signs of the onset of puberty include genital and pubic-hair growth, as well as testicular enlargement.

The causes of the shift toward an earlier onset of puberty are unknown, but some contributing factors could include excess weight or endocrine-disrupting chemicals found in the environment, both which can interact with the body's hormones.

However, it is unclear whether those theories hold water. Excess fat and endocrine-disrupting chemicals can expose boys to greater amounts of estrogen, which should have the effect of delaying puberty, Panagiotopoulos said. In fact, some studies have found that excess body fat is linked to delayed puberty in boys.

Other factors, including genetics, nutrition, demographics and socio-economic background, all probably play some role determining the onset of puberty. More research is needed to confirm whether pubertal onset is skewing younger in Canada and, if it is, to determine what is causing it and what impact it may have on future development.

The best advice for parents, according to experts, is to start a discussion about puberty and the changes that come with it before it happens. "Parents need to talk to kids about what's happening," said Dr. Debra Counts, an associate professor of pediatrics and division head for pediatric endocrinology at the University of Maryland School of Medicine.

"I think it can be challenging for boys," Panagiotopoulos said. "They might be growing taller and looking a little bit more mature, but their brain isn't quite ready for those changes and they're not psychologically ready to handle them."

Schools should also be ready to adapt and accept that changing behaviour in nine- and 10-year-old boys, such as increased aggression, could be a sign of early puberty onset, not a behavioural problem, pediatric health experts say. "I think that's where everyone needs to be aware," Panagiotopoulos said.

It's unclear what, if any, long-term health consequences may be linked to an early onset of puberty in boys. That is one area researchers will need to focus on as they work to better understand this trend.

It is important to note that if children experience the onset of puberty at unusually young ages, their parents are typically advised to consult a doctor to determine whether any underlying health conditions are the cause. For girls, this usually means pubertal onset before the age of 8, while in boys, it means before 9.

Parenting advice

Going through puberty at a younger age could make a confusing time even more challenging for many adolescents, so the key is to make sure they understand what is going on before it happens.

"You don't want to do it as they are going through it," said Anthony Wolf, a clinical psychologist and author who writes a parenting column in The Globe and Mail.

Although many parents think that children are too young or sensitive to have a discussion about puberty at, say, the age of 6 or 7, it is actually ideal for many reasons, Wolf said. That's because children can take in the information without the awkwardness that comes at older ages.

His advice is for parents to briefly and matter-of-factly tell their children what changes they can expect in their bodies in the coming years. They don't have to sit down a six-year-old and explain every facet of the emotional and physical changes they may experience throughout puberty. The important thing is to give them a clear idea of the basic physical changes they will be experiencing. It helps them understand and be more aware of what is happening, Wolf said.

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