Cover image for Early puberty in girls : the essential guide to coping with this common problem
Early puberty in girls : the essential guide to coping with this common problem
Kaplowitz, Paul.
Personal Author:
First edition.
Publication Information:
New York : Ballantine Books, [2004]

Physical Description:
viii, 198 pages : illustrations ; 21 cm
Format :


Call Number
Material Type
Home Location
Item Holds
RJ144 .K37 2004 Adult Non-Fiction Non-Fiction Area
RJ144 .K37 2004 Adult Non-Fiction Open Shelf
RJ144 .K37 2004 Adult Non-Fiction Young Adult

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The definitive book about early puberty in girls--what it is, how it happens, when to be concerned, and how it should be treated. In recent years, the issue of early puberty in girls has become a well-publicized topic. But the messages from the medical establishment and the media have been confusing and often conflicting. Now Dr. Paul Kaplowitz, a pediatric endocrinologist who has treated children for more than twenty years, has written a comprehensive and completely accessible book on the subject--the perfect guide for parents concerned about their daughters' premature development. Inside, they will find the answers to many questions, including • What are the hormonal and physical changes of normal puberty? Breast development, pubic and underarm hair, body odor, menarche (a girl's first period), and the pubertal growth spurt • How do we know if puberty is starting too early? The age and circumstances under which a girl can mature too soon; why this is occurring earlier than in the past, and why that age is earlier for African American girls • What effects does the early onset of puberty have on the behavior and emotional health of young girls? From anxiety and withdrawal to worries about stunted growth, earlier periods, and earlier sexual activity • Is it because the environment or our fats cells? An in-depth look at the potential culprits: chemicals and hormones in the environment, family relationships, stress, and increasing obesity • To treat or not to treat? The six essential questions whose answers will determine whether treatment is necessary for your early-maturing daughter • How should a family prepare for a visit to a specialist? Important tips for getting the most out of a visit to a pediatric endocrinologist Dr. Kaplowitz also details extensive case histories that will help parents understand the real issues that may appear in girls' lives. Reassuring, authoritative, and thoroughly detailed, Early Puberty in Girls is a must-have book for every parent of a young girl.

Reviews 1

Library Journal Review

News that puberty is starting earlier in girls, especially African American girls, hit the Washington Post and the Philadelphia Inquirer in 1999 and soon after became a major health topic on morning shows and in news magazines. Kaplowitz is the pediatric endocrinologist (Children's National Medical Ctr., Washington, DC) who issued the report, causing the ensuing media storm. He realizes more than anyone that parents need an accessible medical book on this subject. Here, he seeks to answer several common questions, e.g., is puberty really starting earlier? Why? Does it matter? What caused this? Why not in boys? Why black girls more than white? Kaplowitz claims that "no compelling evidence" points to endocrine-disrupting contaminants in the environment. Instead, he leans toward the increased prevalence of obesity in our culture: overweight girls mature earlier than thin ones. Insulin sensitivity in people of color also is a factor. Kaplowitz succeeds at writing clearly and reassuringly for alarmed parents. Recommended for public libraries; so far, this is the only popular discussion of the subject. (Charts and illustrations not seen.)-Linda Beck, Indian Valley P.L., Telford, PA (c) Copyright 2010. Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.



CHAPTER 1 PUBERTY 101 What most parents understand about puberty is based on their own experience with it. Women typically recall the time of their first menstrual period (we use the term menarche when we refer to this event), and men often remember the grade they were in when they shot up four inches and kept outgrowing clothes and shoes. Some people remember puberty as a stressful time, though many of the stresses were likely more related to the difficult process of separating from one's parents and identifying with one's peers than to the hormonal changes themselves. Some mothers I have talked to who had puberty distinctly earlier than their peers recall feeling different or isolated, particularly if they went through menarche by age 10 and had no friends who had been through it before them. However, most parents I talk to do not have enough recollection of the timing and sequence of events their bodies went through between ages 10-12 and 15-17 for it to be of much help in deciding how worried to be or how to advise their children in the event one of them shows signs of puberty at an early age. To really understand what is or is not happening when a young child exhibits signs of puberty, a basic understanding of the physical and hormonal events of puberty is very helpful. In this chapter, I will describe these events in language that is as nontechnical as possible, while setting the stage for the discussion of the mechanisms underlying early puberty in the chapters that follow. I will start with a discussion of normal puberty in girls, followed by a shorter discussion of normal puberty in boys. The Normal Physical Changes of Puberty in Girls Breasts In order to be sure that a girl has started to undergo puberty, there needs to be breast tissue. This sounds simple and quite obvious, but as I will explain later, it is remarkable how often this fact is ignored. In girls who have not started puberty, one can often detect a tiny amount of tissue under the nipple, the breast bud, which is usually no larger than 1Ž4 inch in diameter. It is only when estrogen production starts to increase that the breast bud starts to increase in size. One can also see a thickening and darkening of the skin overlying the breast tissue, called the areola, and often a protrusion of the nipple at the center of the areola. Pediatricians rate breast development using the Tanner scale, developed by Dr. James Tanner. The five stages are defined as follows: Stage 1:Prepubertal; no breast tissue present Stage 2:Breast bud stage: a small mound of breast tissue under the nipple, slight enlargement of the areola Stage 3:Further enlargement of the breast and areola but no separation of their contours Stage 4:Areola and nipple form a separate mound above the level of the breast Stage 5:Fully mature adult breast, with only the nipple projecting above the level of the breast When puberty is in full swing, the amount of time needed to progress from stage 2 to stage 5 is between two and three years. However, with early-maturing girls, the progression is often slower, and as I will point out in the next chapter, very young girls can have stage 2 breast development and not progress at all for many years. In slender or nonobese girls, simple inspection is usually adequate for a parent or a pediatrician to tell if a girl has breast development. However, in overweight girls, this is often difficult, since in the sitting position, fat over the chest can look very much like breast tissue. One clue is that when the girl lies on her back, the fat redistributes itself over a wider area and what looks like breast tissue largely disappears. The most reliable method, however, is simply palpating, or feeling for breast tissue with one's fingers. Breast tissue feels firmer and rounder than fat tissue and is located directly under the areola. My general rule is that if the diameter of the breast tissue held gently between the thumb and index finger is over 1Ž2 inch, it is likely that the breasts are starting to enlarge. However, it often takes a few months of observation to be sure. Pubic and Underarm (Axillary) Hair The greatest source of confusion among both parents and primary-care physicians is the meaning of the appearance of pubic hair in a young child. We are talking here about not the fine, light-colored hair similar to what may exist on other parts of the body, but dark and (if it is long enough) curly hair on both sides of the opening of the vagina and eventually above the vagina (an area called the pubic symphysis). We also use the Tanner scale for describing the extent of pubic hair growth as follows: Stage 1:No pubic hair Stage 2:Sparse growth of long, dark hairs, straight or slightly curled, along the sides of the opening of the vagina Stage 3:Hair is darker and curlier and now spreads thinly over the pubic symphysis Stage 4:Hair is thicker and looks like what one would see in an adult, but covers a much smaller area Stage 5:Hair is adult in quantity and type, distributed like an upside-down triangle It is important to understand that growth of pubic hair has nothing to do with estrogens made by the ovaries. It is due to male-type hormones made in the adrenal glands, which we refer to as adrenal androgens. The adrenal glands are small but vital glands that sit just above the kidneys; they also make cortisone (a hormone that is essential to life) and a salt-retaining hormone. Because in many children pubic hair appears at the same time as other signs of puberty, there is a widespread belief that pubic hair equals puberty. The truth is that pubic hair can appear several years before other signs of puberty (e.g., breasts) or can appear at a later time. Axillary hair is thought to reflect the same hormone changes that cause pubic hair, though in most girls detectable axillary hair will appear three to six months after pubic hair. What regulates the ability of the adrenal glands to increase androgen production is still not clear, but we know that the hormones that stimulate the ovaries to make estrogens are not involved. In the past, most girls were said to develop pubic hair between ages 8 and 12, but more recently its appearance between ages 5 and 8 has become increasingly common. Body Odor Another sign thought to be characteristic of puberty is development of an adult-type body odor, originating entirely in the underarm area, or what physicians call the axilla. Although this phenomenon as it occurs in children has received little scientific attention, I have concluded after years of talking to parents that the development of body odor, like pubic hair, is closely related to the increase in adrenal androgen secretion. This is because the timing of the onset of body odor is usually close to the time of appearance of pubic hair. Sometimes parents report detecting the odor three to six months before any pubic hair is evident. How adrenal androgens might influence the nature of what comes out of our axillary sweat glands is not clear, nor is it clear what the role of axillary odor in human reproduction might be. It may have evolved as a way for humans to recognize when another member of the species is close to reproductive maturity. Pubertal Growth Spurt One of the most dramatic changes occurring during puberty is the rapid growth that typically becomes apparent within a year after the appearance of breast tissue and is directly related to increased estrogen and growth hormone production. Prior to puberty, the normal rate of growth is about 2 inches per year, but this increases to about 4 inches per year during the most rapid phase of the pubertal growth spurt. In many girls, this occurs sometime between ages 10 and 12, but there is a great deal of variability. Men may recall that when they were in fifth or sixth grade, the girls shot past them in height, only to be passed two to three years later, when the guys finally had their growth spurt. One occasional source of confusion is when we see what looks like a growth spurt in children who are very overweight, since overweight kids often grow more rapidly than normal. However, if the breasts are not enlarging, this is not a true pubertal growth spurt. Menarche For years, the average age at which white girls have their first menstrual period has been about 12.7 years, though a recent study based on data collected between 1988 and 1994 suggests that this has decreased slightly to 12.5 years. In black girls, the average age of menarche is 0.4 to 0.5 years earlier, or a little over 12 years. Again, there is a great deal of variability from child to child, with some normal girls starting their periods as early as age 10 and others not starting until 15. Genetic factors are important, in that mothers who started their periods early are more likely to have daughters who start early. Another important factor is body weight and fat content. Numerous studies have shown that overweight girls have menarche earlier1,2 and thin girls, especially thin, athletic girls (particularly gymnasts, competitive swimmers, and ballet dancers), start later.3 In the landmark study of Marshall and Tanner, 192 white British girls were examined several times as they progressed through puberty. Published in 1969, the study showed that the average time it takes to progress from Tanner stage 2 breast development to menarche (which typically occurs at Tanner stage 4) was 2.3 years.4 However, there is reason to believe that more recently the interval has gotten longer. One study from Spain showed that the interval from the start of breast development to menarche averaged 2.9 years in early-maturing girls but only 1.5 years in late-maturing girls.5 Although reliable data has not been published recently in the United States, it is reasonable to assume that with girls who mature earlier, the average interval between appearance of breasts and menarche may be closer to 3 years than to 2.3 years. The onset of menses also signals that the pubertal growth spurt has nearly been completed. Most girls grow only 1 to 4 inches after their first period, with early-maturing girls having more growth left at menarche than late-maturing girls. The Normal Physical Changes of Puberty in Boys Testicular Enlargement It is widely agreed that the most reliable sign of the onset of puberty in boys is enlargement of the testes. In prepubertal boys, the testes measure 1 inch (2.5 cm) or less in their greatest diameter; an increase to 11Ž4 inches (3 cm) or more is a reliable sign that the puberty hormones of the pituitary have started to kick in. (In girls, there is a similar increase in the size of the ovaries, but since we can't measure the ovaries unless we do an ultrasound study, this change is not as helpful in assessing female puberty.) In most boys, this starts to occur between ages 10 and 13. Pubic and Axillary Hair Pubic and axillary hair can appear before, at the same time as, or later than testicular enlargement, because this development is driven by adrenal androgens, at least in the early stage. Thus it is not a reliable sign of the onset of puberty. In the later stages of puberty, increases in testosterone contribute to the increase in the amount of pubic hair. Genital Enlargement, Facial Hair, and Voice Change The growth of the penis in both length and diameter and the enlargement and reddening of the sac surrounding the testes (the scrotum) are good signs that production of testosterone is increasing. This tends to occur at least six to twelve months after enlargement of the testes is first noticeable, though there is a lot of variability in the timing. Hair in the mustache and beard area and deepening of the voice are also changes mediated by testosterone, though they take longer to become obvious. Pubertal Growth Spurt This occurs on the average two years later in boys than in girls, and the average age of the growth spurt is between 13 and 14 years, usually at a time when the changes mentioned above are well established. Growth is also completed about two years later in boys, typically by age 16 or 17. It is a little known fact that most of the 5-inch difference in average adult height between boys and girls can be attributed to an extra two years of growing in boys at the prepubertal growth rate of about 2 inches per year. The rate of growth at comparable stages of maturation is almost identical between the sexes. The Hormones of Puberty Gonadotropin-Releasing Hormone The hormone believed to initiate most of the sequence of events described above is a tiny protein or peptide manufactured in a small part of the brain called the hypothalamus. It is made up of only ten amino acids (the building blocks of proteins) and is called gonadotropin-releasing hormone, or GnRH for short. There is a cluster of cells (called a nucleus) within the hypothalamus that releases brief pulses of GnRH about every two hours. Instead of the GnRH going into the general circulation, it is released into special blood vessels that travel down a thin structure called the pituitary stalk, which connects the hypothalamus to the pituitary gland. The release of GnRH in pulses, as I will explain elsewhere, is critical to normal reproduction. Although the subject of intense study (mostly using primates), the mechanism by which the pulsatile release of GnRH is largely suppressed by critical areas of the brain for all the years between infancy and puberty is still a mystery. We can be grateful, however, that nature figured out a way to restrain our species from becoming reproductively mature at a time when our brains and the rest of our bodies would not be ready to cope. Gonadotropins When pulses of GnRH are released into blood vessels flowing into the pituitary, they locate and bind to specific receptors on key cells in the pituitary, a bean-sized master gland located at the base of the brain and straight back from the bridge of the nose. The pituitary makes at least six different hormones, including growth hormone, but for now we will concern ourselves only with the cells called gonadotropes, because their job is to produce two key hormones, which we refer to as the gonadotropins (meaning "causing the gonads to grow"). They are called luteinizing hormone (LH for short) and follicle-stimulating hormone (FSH for short). Because GnRH is secreted in pulses about every two hours, when puberty gets under way the pituitary responds by secreting a pulse of LH and a smaller pulse of FSH about every two hours. In early puberty, it has been found that the increase in LH and FSH takes place mainly during the nighttime hours, whereas later in puberty, LH and FSH are increased all day. Excerpted from Early Puberty in Girls: The Essential Guide to Coping with This Common Problem by Paul Kaplowitz All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.