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Precocious puberty

At Stanford Medical School with Morgan Theis talking to Dr. Laura Bachrach talking about precocious puberty. Created by Sal Khan.

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Video transcript

i'm here at stanford medical school with Morgan Theis and Dr. Laura Bachrach and they're going to teach us some things. Okay, so what are we going to learn about today? I'd like to talk about precocious puberty it seems to be on the minds of many parents these days they worry that their child is developing too early, they worry their child is going too small as a result, they worry their child is going to get picked on, and they worry they might have done something wrong. Fed the child the wrong food, or exposed them to the wrong videos, to cause this all to happen. So could we just talk about what precocious puberty means, it almost sounds like they've done something too soon, is that correct? It's exactly true. The normal process of puberty, in a girl, we think, we used to think, started around the aged of 10, with a little bit of breast development. And around 6 months later, the girls would get a little bit of pubic hair, and around the age of 12 and 3/4 to 13 they'd get their first period. Ok. In boys, we used to think, the process was starting a little later, at about 11 and a half. The boys would get some enlargement of the testes. They'd get some pubic hair about a year later. And by age 15 or so, they'd be mature. We have a definition of what's precocious, uh, when there's signs of puberty before 8, in a girl, or before 9, in a boy. Ok. So, 8 or less in a girl, would be precocious, and that's for the breast development? For any signs of puberty: the breasts, the pubic hair or the period would be precocious if it happened before the age of 8 in a girl. And in a boy, before the age of 9. Now this has become a little bit controversial because there was one very large pediatric study that involved over 17 000 girls that found that as many as 25% of african american girls would have sign of puberty before 8, and as many 7% of the white girls had some signs of puberty before age 8. But we're still basically using these guidelines. Not to say that this is definetely abnormal, but this is something we're going to evaluate. If we see signs of puberty before those age landmarks. Ok, so it sounds like there's a lot of variability, it's kind of hard to know in any individual case, whether it's normal or not, but we have to have some kind of threshold for which we're going to work someone up to make sure everything is normal. You hit on a really important word. And that is variability. And a lot of this variability, uh, is determined by genetics. So part of what we always need to know is the timing of development in the family. So when did mom get her first menstrual period, when did dad get his puberty and growth spurt? So that's part of it, genetics, and we need to know that, take that into account: If mom had her first period at 10 and started her breasts at 8 it might be perfectly normal for her daugher. If mom's period were at 14 and her daughter has breast development at 7 and a half it's more worrysome. Ok. Ok, the second factor that seems to be contributing, potentially, is the overnutrition of our young people. Oh, yes. And in the particular study that I mentioned to you, where they looked at over 17 000 children, at least for the white population, the could explain the earlier signs of puberty as an association with a high body mass index. So it looked as if, if you overnourish your child you may speed along their growth, and eventually, potentially, speed along the onset of puberty. Now, this did not hold up as an association in the african american population, so there's other factors going on there. But that's something that we rtake into account. THe bottom line is, the child may present with some signs of early puberty, mom or dad get worried, they go to the pediatrician, and the pediatrician has to decide what's going on. Ok, now, JUST Backing up a little bit, is this a problem? I mean, what's the problem with, say, a 7 year old girl starting puberty, or, uh, an 8 year old boy starting puberty early? I imagine there could be some social implications (as you mentionened) but what are sort of the things we worry about? Well, that's an important question, because it comes up not only how far do we go to evaluate them, but how far do we go to treat them? So, one of the concerns parents have, relates to their final height. So, if they start their growth spurt early in life, and close it off early in life, are them gonna cheat themselves out of some final height? Right. So height is a concern. And its impact really depends upon how young the child is. A three year old going into puberty is definetely going to end up short if we don't do something. A seven and a half old girl is probably not going to be altered by this in terms of height. The second concern is definetely what you brought up, in terms of social concern. Parents worry their child may behave in an older way, or be treat in a way that they're not quite ready for. They mey get unwarranted attention from people because they look older. And there is even potential concern for abuse, sexual abuse. Um, right. So those are the usual parental concerns for why they bring the child in. The other concern they have is, often "what am I doing wrong". There are a lot of questions about "should I have fed my child organic food?" "what about the soap i was using?" "what about the soap operas my child was watching?" You know, they're really concerned about something they might have done. And they worry about these additives in ourplastics, in our theeth sealants, etc... They worry about evils inour environment. Okay. So things that you address in the visit that you have with them are definetely some of the, the concerns that parent have about what they could have done differently. Exactly. We start out, assessing in a sort of a systematic way. The first question we want to know, is when did this all start? And what did they notice. And it's really important to break down the signs of puberty, because different hormones contribute to the different signs. For example, in a girl, if she is presenting with some body odor, some acne, and some pubic hair, but no signs of any breast development, that leads us down the road to worry about what we call her androgens or her male hormones. If a girl comes in with just breast development but none of the body hair or body odor, we think, aha! she's been exposed to estrogens. And so we get a lot from the physical exam in terms of thinking what hormones to go after. okay, so even though the definitions of precocious is just any of these different physical developments happening too soon, the combination that you see is going to direct what yo uthing is going on wit hthem clinically. Exactly. Ok It will make us more or less worried and it will take us down one avenue or another, thinking about what could be wrong, what level of abnormality in the hormone system is at work. Ok. Can I ask you a question, just curious, so what are the most common diagnosis given to people coming in with their kids, that are concerned for precocious puberty? The common diagnosis, is "variations are normal". Aha. There is a condition called "isolated premature adrenarche" which is a fancy doctor way of saying the adrenal glands producting their hormones, we see pubic hair, underarm hair, and acne. Uh... We also can see isolated breast development in little toddler girls that's not concerning. So that would just go away, or? Yes. Typically that begins between six months and two years and goes away. But even within the more full blown cases, where we're seeing breast and the pubic hair in a girl, or the enlagrement of the testes and the pubic hair in a boy, where's it's full on, full blown puberty, it may be idiopathic, or not pathological. We think that in girls, who develop fully, 95% of the time, even if they have the full blown puberty, it's idiopathic, or not pathological. Whereas in boys, about 50% of the time, there is pathology. So the condition is less common on boys, but when it occurs in boys, it's more worrisome. Oh, interesting. So it's less common for boys to have any signs of precocious puberty, but when it does happen you worry more. Exactly. Because it's more likeyl to be something bad. Exactly. Ok. So I'm guessing as an endocrinologist, once you've sort of ruled out the normal things, then you start th then you start thinking more about sort of what's going on in terms of all the different hormones that are controlling the se things, which maybe is something that we'll talk about in a different lecture exactly. is there any other sort of general things that you wanted to adress when we'll just talking about... I think the general advice I would give to a parent if see signs of puberty in their child, before 8 in a girl, before 9 in a boy, they should at least question their pediatrician about it, uh, and the pediatrician should do a complete exam, and the other factor that needs to be looked at carefully is growth, because a child who is truly in puberty will have a growth spurt. So, those are things that parents can be aware of at home, but I think it's important that the parent asks the pediatrician about it, if they are concerned. Ok, well thank you so much.