many of the changes associated with puberty, such as deepening of the voice, facial hair, enlargement of the penis and scrotum, and sperm production. Men will make testosterone throughout their lives, but as they age the body may make less of it. After puberty, men have the potential to make sperm their entire life. However, men are not able to make sperm if the body is not able to make testosterone. FEMALES The ovaries are the primary reproductive organs in females. Immature eggs are present in the ovaries before birth and females are born with all the eggs they will ever have. The body is not capable of making more eggs. During puberty, hormones from the brain send signals telling the ovaries to begin maturing a small number of eggs. In most cycles, one of these eggs will be released each month. If the egg is not fertilized by sperm, a woman will have her period. Estrogen and progesterone are hormones made by the ovaries once a young woman starts puberty. They are also necessary for breast growth and other changes that happen during puberty, such as widening of the hips and pubic and underarm hair growth. Menopause, which typically occurs when a woman is in her 50s, takes place when the ovary no longer contains any eggs. When this happens, the ovaries will no longer produce estrogen and progesterone and the woman will stop having a period. PREGNANCY Pregnancy occurs when an egg is fertilized by sperm. This typically occurs during sexual intercourse, but some women may require medical intervention (such as in-vitro fertiliza- tion) to have children. Pregnancy cannot occur if a male or female has not yet reached puberty or if the body is not able to make the hormones needed for reproduction. n EFFECTS OF CANCER TREATMENT ON MALE REPRODUCTION AND PUBERTY Children diagnosed with cancer may have problems with fertility later in life.This is a potential long-term side effect of the cancer treatment. The reproductive health of children treated for cancer depends on many factors, including the age at the time of diagnosis, total dose and types of chemotherapies, and the combination of chemo- therapy and radiation. Radiation and chemotherapy given together may increase a child’s risk for fertility problems. Other problems children may develop after cancer treatment include: • precocious puberty: puberty that begins before age 9 years in boys • delayed puberty: puberty that begins after age 16 years in boys • arrested puberty: puberty that has started but then stops before completion • testicular dysfunction • infertility.
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