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 | The production of these hormones increases gradually until sexual maturation is met. | |
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| Some boys may develop gynecomastia due to an imbalance of sex hormones, tissue responsiveness or obesity. | |
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| Primary sex characteristics are those directly related to the sex organs. In males, the first stages... | |
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| ...of puberty involve growth of the testes and scrotum, followed by growth of the penis. | |
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| At the time that the penis develops, the seminal vesicles, the prostate, and the bilbo-urethral glands also enlarge and develop. | |
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| Boys are generally fertile before they have an adult appearance. | |
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