Bigger Kids

All about hormones

Everything you ever wanted to know about puberty

By Teresa Pitman
All about hormones

You have survived the tumultous toddler years and the transition into school, and your parenting life has settled into a manageable routine. Don’t worry that you’ve gotten into a rut. Nature has plans to shake things up for you. We call it puberty. OK, you’re familiar with the concept. You went through it once yourself, after all. But now you need to prepare for the roller-coaster ride from a whole different perspective. So, with thanks to paediatricians Jorge Pinzon of Calgary and Cathleen Steinegger of Toronto, here’s the nitty-gritty on puberty: the hormones, the hair, the mood swings and a few unexpected twists. The boys

Order of events Get ready, get set: Puberty normally begins for boys between ages nine and 14 and can last anywhere from two to five years. Your son will probably be pleased with the first sign — enlargement of the testicles. Then his pubic and underarm hair will start to grow, with body odour and oily skin following soon after. About a year after the onset of puberty, he’ll start producing sperm, and may have some “wet dreams.” Then your son will grow taller (many boys grow quite rapidly), sprout facial and chest hair and develop a deeper voice (after an initial crack and waver of the vocal cords).

How it happens We tend to chalk these changes up to those weird and wonderful hormones, and indeed, they are the instigators. The hormones involved in puberty get activated through a chain reaction that starts with the hypothalamus, a part of the brain that controls a bunch of important functions, such as body temperature and sleep cycles. Nobody really knows what triggers the hypothalamus, but when the time comes, it sends a memo to Puberty HQ (better known as the pituitary gland). The pituitary then sends out its own messages to the testicles and adrenal glands, which start pumping out the hormones, in particular testosterone, that start all the changes.

Unexpected changes in boys

Twisted testicle or testicular torsion This happened to one of my sons, and it’s about as bad as it sounds. The testicle hangs from a cord and is quite loosely attached to the scrotum, so it can become twisted. It’s most common during puberty because the testicles are growing. The symptoms: pain (and lots of it), swelling and sometimes nausea and vomiting. It’s very important to have your son examined by a doctor immediately because the twisting cuts off the blood flow to the testicle, and he may need emergency surgery.

Breast development (gynecomastia) No, you’re not accidentally looking in the girls’ section. Up to 70 percent of boys going through puberty will develop, well, breasts. You know, “man-boobs.” It’s not uncommon for one side to be larger than the other, and they’re typically bigger in boys who are overweight. While a boy’s breasts usually disappear as puberty continues, they tend to stick around in men who are overweight (although they will shrink with weight loss). In some rare cases, breast reduction surgery is recommended at the end of puberty.


Too-tight foreskin (phimosis) Paula Baker’s* son developed some small lumps on his penis at age 12. The doctor diagnosed a too-tight foreskin and recommended circumcision. “My son really didn’t want the surgery,” says the Dartmouth, NS, mom. “So we did some more research and found that often a tight foreskin will loosen up and begin to retract properly as puberty continues. And that’s what happened.” How common is this? Between one and eight percent of boys will experience it. Most infant boys have a non-retractable foreskin, but as the penis grows with puberty it sometimes gets tighter. A teenage boy with phimosis should be told to retract the foreskin frequently to increase its elasticity. Some cases are treated with steroid creams, and sometimes surgery is needed.

*Names changed by request

The girls

Order of events Are girls hitting puberty younger? Well, yes and no. Breasts and pubic hair seem to be showing up earlier than in the past, but the first menstrual period isn’t. Expect your daughter’s breasts to start developing between ages nine and 10, on average, and her first period to begin roughly between ages 12 and 13. Of course, some girls start a bit earlier and some a bit later.

How it happens Just as with boys, puberty in girls is the result of a chain reaction of hormonal messages. The first of these is delivered to the ovaries, which promptly get into the estrogen-production business. Estrogen’s first tasks: creating small, tender lumps (“breast buds”) under one or both nipples as the first step in growing breasts, and the sprouting of pubic hair (which will be soft at first but gradually grow thicker and curlier), underarm hair and increased hair on the legs.


Estrogen also changes a girl’s shape, enlarging her hips and making her body more rounded, sometimes causing a little panic in girls who are worried about their weight. Remind your daughter that it is normal and healthy for her to put on weight, increase body fat and develop a womanly shape at this time in her life.

Paula Baker gave her daughter Helen, now 15, a basket of “girl stuff” as soon as she noticed the earliest signs of puberty. “I packed up pads, tampons, deodorant and acne face wash — but also fun stuff that she likes, such as lipstick and nail polish,” says Baker. “She kept it all on a shelf in her closet and even before her period started I noticed that she’d opened and experimented with the pads and tampons.”

Unexpected changes in girls

Precocious puberty When puberty begins significantly earlier than age eight in girls and nine in boys, it is called “precocious.” Nina Peterman* of Toronto noticed breast buds on her daughter Rachel’s chest when she was still a preschooler. At eight, Rachel had pubic hair and already needed deodorant and a bra. Peterman took her to a paediatric endocrinologist, who prescribed hormone injections to slow down her development in order to let her grow taller. (Once menstruation starts, girls don’t grow much.) Rachel’s treatments will continue until she is at least five feet tall.

Lopsided breasts It’s common — if a little embarrassing — for one breast to develop more quickly than the other, and for some girls this difference is quite noticeable. Some padding in the bra can even things out temporarily. Usually, the slower-developing breast “catches up,” but some adult women continue to have breasts of different sizes.


Stretch marks We often think of stretch marks as part of having a baby but, in fact, they can appear at any time of rapid growth — and that’s exactly what puberty is. If your daughter’s body grows faster than her skin can stretch, she may end up with red or purple lines on her hips, breasts or tummy. While the marks are quite visible at first, they will fade to a whitish or silvery colour and become much less obvious over time. (Boys can get them too, but it’s more common in girls.)

Depression Depression is uncommon in young children, and generally occurs equally often in boys and girls. But once puberty is under way, the rate of depression zooms higher, and girls are twice as likely to experience it as boys. A 2004 study from the University of Victoria found that about 21 percent of teen girls between 13 and 19 had been depressed, compared with about 10.7 percent of boys the same age.

*Names changed by request

More suprises — for boys and girls

Scoliosis Some kids are born with scoliosis, or a curve in the spine. The condition ranges from mild to serious; at its worst, it can lead to disabling deformities. If your child has scoliosis, it will probably become obvious when she reaches puberty. Your family doctor will look for signs of scoliosis during routine checkups, or you might notice a curvature in your child’s back when she wears a bathing suit, for example. If this happens, be sure to let your doctor know; while most cases are mild, it’s probably worth having your child examined by a specialist.


Myopia You know how your teen is very self-conscious about his looks? Here’s something he won’t be thrilled about: Many people get their first pair of glasses during puberty. Just as the body is growing, so are the eyes. Too much lengthening of the eyeball can lead to myopia, or nearsightedness, which means that a person has difficulty seeing faraway objects.

Sleep issues At puberty, the natural timing of the sleep cycle begins to shift. The baby who wouldn’t stay in her crib past 6 a.m. now won’t get out of bed when the alarm goes off. What your teen has been telling you is true — it’s normal for her to go to bed late and get up late. Unfortunately, most schools don’t accommodate this schedule and many teens are chronically sleep-deprived. This doesn’t help with the moodiness many kids go through in their teen years. And speaking of moodiness...

Adults tend to make fun of teen mood swings, and it can be hard not to laugh just a little when your daughter arrives at breakfast like a storm cloud, hollers at you for 10 minutes because you didn’t wash the T-shirt she’d planned to wear, and then answers her cellphone with a sweet: “Oh, hi, Vera. Yeah, everything’s cool.” But while her friends can make light of these moody moments — after all, they’re going through the same thing — parents must recognize that these intense feelings are real and often hard to manage. So try not to roll your eyes.

Terry Stafford of Fort Langley, BC, has three daughters who are all now on the other side of puberty. “Looking back, I can see how much more complicated emotionally they became during that period,” she says. “One daughter had a best friend who practically felt like part of the family, she was always around. Then one day she moved on to a new group of friends and cut my daughter off entirely. That was incredibly painful for her, and I felt helpless.”

Stafford found that the secret to keeping the lines of communication open was listening with respect and not getting upset (or at least not letting it show). “I felt I walked a thin line between being non-judgmental and wanting to give more advice and guidance. One thing that seemed to work was to give my ‘wise words’ in one short statement and then just let it drop,” explains Stafford. Her middle daughter later commented that her mother’s “nuggets” always made her think.


And...(drum roll please)...then there’s sex. Vicki Cross* of Peterborough, Ont., was shocked to discover a note from a boy in her 13-year-old daughter’s backpack that got pretty explicit about what he wanted to do with her. “I realized that I needed to talk to her now about sex and relationships,” Cross says. Discussions about sexuality should really begin before puberty, but if you haven’t brought it up before, now’s the time. On the other hand, don’t panic just because your son starts talking about his “girlfriend.” Their relationship may be more casual than it sounds. “Helen’s 15, and she has a boyfriend,” says Paula Baker. “She told me about six weeks ago that they were going out, but actually they’ve only been out together once since then. What they really do is talk for hours on the phone and on MSN.”

Finally, while it may seem as though friends are of the utmost importance at this stage, all the research shows that family remains a vital and welcome support system for most teens. Yes, they still need you, still love you and together you can survive the ups and downs of puberty’s changes.

*Names changed by request

This article was originally published on Aug 04, 2008

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