Health and medical information

Recently, one group of doctors looked at PSA, transrectal ultrasound and digital rectal exam. They found these tests to be unhelpful, questioned their cost-effectiveness, and concluded that “screening for prostate cancer represents a clinical dilemma with no clear evidence to suggest decreased mortality from any diagnostic test.” Critics have contended that PSA test results could prompt thousands of men to have unnecessary and expensive diagnostic procedures, which might lead to unnecessary surgery One leading magazine told its readers that PSA “could do more harm than good by leading to premature biopsy or treatment”; that the biopsies it prompts are “an infection waiting to happen” (actually, this is not the case; see the “Biopsy” section in this chapter); and that the PSA test can be wrong “four times out of ten.”

Doctors at a National Cancer Institute meeting took the PSA arguments several steps further. Many men over age 50 have cancerous cells in their prostates, they said, but just a small percentage of men die from prostate cancer. Most prostate cancer, they argued, is slow-growing and causes no problems. As one doctor told a New York Times reporter: “There are millions and millions of American men who have this cancer and are never ill, yet these powerful tests (PSA) are going to detect them. If the PSA is elevated, the chance that it is prostate cancer is relatively small. But even if it does represent prostate cancer, there is no way to know whether testing and treatment change the outcome or improve the health of patients.” Some doctors went so far as to state that men should sign informed consent agreements before getting a PSA test. “The information you get back can lead you down a cascade of interventions that can be deadly,” one doctor said, citing controversial statistics from a Medicare study for incontinence, impotence, rectal injury, and death resulting from surgery to remove prostate cancer.

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As we’ve explained, a girl’s first ovum isn’t fertilized by a sperm. It doesn’t plant itself in the uterine lining; instead, it simply disintegrates. Because the ovum hasn’t been fertilized, there’s no longer any need for the thick lining that has grown on the inside walls of the uterus, so the uterus begins to shed the lining. The tissues of the bloody lining begin to break down and turn very liquidy. The bloody and liquidy tissue collect at the bottom of the uterus. They dribble out of the opening in the bottom of the uterus that leads to the vagina. Then the blood and liquid flow down the vaginal walls and dribble out of the vaginal opening.

When a girl begins bleeding from her vaginal opening, we say she is menstruating or having her menstrual period. A girl generally has her first menstrual period between the ages of 9 and 16. The average age is about 13. It takes about three to seven days for the uterus to shed the lining completely. Altogether, about half a cup of blood comes out of the girl’s vagina during her menstrual period. While she’s bleeding like this, a girl usually wears a pad of cottonwool, called a sanitary pad or towel, inside her underpants to catch the blood. Or she may insert a cottonwool plug, called a tampon, into her vagina to absorb the blood. She changes this pad or tampon several times a day.

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Yes, many people masturbate even though they have regular sex partners. They may masturbate privately (that is, when they’re alone) or they may include masturbation as part of their sex lives with each other. They may masturbate before they have intercourse as a way of ‘warming up’ or getting ready. Or they may masturbate instead of having intercourse, especially if the couple doesn’t want to take the risk of the woman getting pregnant. (Unless a man ejaculates in the vagina or near the opening of the vagina, the sperm can’t get into her uterus and Fallopian tubes to fertilize the ovum.) If a man ejaculates before the woman has an orgasm, masturbation can be a way for her to have an orgasm even though his penis is no longer erect and they can’t continue having intercourse.

If a boy doesn’t masturbate or have sexual intercourse, what happens to all the sperm?

If a boy doesn’t ejaculate, either through masturbation or intercourse, one of two things may happen. As the ampulla becomes full, the sperm may simply dribble into the urethra, be mixed in with his urine and be eliminated from his body when he urinates. Or he may have a wet dream.

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The vas deferens winds up over the bladder, the hollow, pouchlike organ where urine collects. Then the tube widens or flares out. The widened or flared-out portion of the tube is called the ampulla. The ampulla is a sort of ‘sperm storage tank’ or reservoir, where sperm are kept until they’re ejaculated.

The seminal vesicle-Just at the lower part of the ampulla, the seminal vesicles are connected to the vas. You have two seminal vesicles, but you can see only one in Illustration 18. Seminal refers to sperm, and ‘vesicle’ means ‘little sac’, so together the words mean ‘little sperm sac’. The seminal vesicles got their name because scientists once thought that sperm were stored there until they were ejaculated. We now know that sperm are stored in the ampulla, but the name hasn’t been changed.

Even though they don’t store sperm, the seminal vesicles have an important job. They make the white sticky fluid called semen, or seminal fluid, that spurts out of your penis when you ejaculate. Mixed in with this fluid are millions of sperm from your ampulla. But sperm are so tiny that they account for only about one-tenth of the teaspoon of milky fluid that comes out when you ejaculate. The other nine-tenths of your ejaculate is composed mostly of fluid from the seminal vesicles.

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If the increase in the size of your penis and testicles and the growth spurt were the only things that happened during puberty, Dane and I could have ended this book right here. But, as you may have guessed, there are also other changes that go on in your body during puberty. In this chapter and the next, we will be talking about some of these other changes.

The role of hormones-You may be wondering what causes all these changes. The fact of the matter is that no one knows for sure, but we do know that it has something to do with hormones. Hormones are substances that are made by parts of our bodies called glands. The hormones made in our various glands travel to other parts of our bodies and tell those parts how to develop and grow, or how to work and behave properly.

Our bodies have a number of different glands making dozens of different hormones, most of which have long, tongue-twisting names that you can hardly pronounce, let alone spell. You could go crazy trying to remember the names of all these glands and hormones. But we don’t want you to go crazy, so we’re going to talk about only the glands and hormones that have the most to do with puberty.

Puberty starts in your brain. A few years before your sex organs start to grow larger or you start to go through your growth spurt, glands in your brain start making larger and larger amounts of certain hormones. One of these glands in your brain is called the pituitary gland. The pituitary makes a hormone that gets into your bloodstream and travels to your testicles. As you get older, your pituitary sends more and more of its hormones to your testicles. Your testicles are also glands. The hormones from your brain cause your testicles to make hormones of their own. The most important hormone your testicles make is testosterone.

As you begin to go through puberty, your testicles (in response to greater amounts of pituitary hormones) make increasing amounts of testosterone. The testosterone travels to other parts of your body and tells those parts how to grow and develop. For instance, it is testosterone that causes your penis, testicles and scrotum to grow larger. Testosterone is also responsible for the growth of those curly, crisp pubic hairs. In fact, testosterone plays a role in almost all of the changes we will be talking about in this chapter and the next.

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Doctors have divided the growth and development of the genital, or sex, organs into the five stages. You may be in one of these stages or you may be between one stage and another. See if you can find the stage you are closest to.

Stage 5

This is the adult or fully grown stage. The testicles are usually about 45 mm (13A in) long, and generally between 16 and 27 ml (3 1/5 – 5 2/5 teaspoons). The scrotal sac is also fully developed by the time a boy reaches this stage. And the skin of the scrotum and penis has become even deeper in colour.

A grown man’s penis is usually 83-108 mm (3 ¼- 4 ¼ in) in length. When a man or boy has an erection, his penis gets temporarily larger. The largest erect penis ever recorded by a doctor was 304 mm (12 in) long. The smallest was 120 mm (4 ¾ in). Ninety out of 100 men will have a penis that is between 127 and 178 mm (5-7 in) in length when it is erect, with the average length being about 160 mm (6 ¼ in). The smaller a penis is when it is soft, the more length it tends to gain when it becomes erect. For example, a man with a penis that measures 75 mm (3 in) when it is soft may add as many as 83 mm (3 ¼ in) when his penis becomes hard. A man with a penis that measures 108 mm (4 ¼ in) when soft might add only 50 mm (2 in) during an erection.

Thus, even though the lengths of their penises were different when they were soft, both men would have a 160-mm (6 ¼ in) penis when they had erections.

The penis may also get temporarily smaller from time to time. You may have noticed that your penis gets a little smaller if you jump into a cold bath or shower. Cold weather, being really tired or feeling nervous may also make your penis shrivel up a bit. Any of these things may also make your scrotal sac pull up closer to your body and seem smaller temporarily. In old age the penis tends to become a bit smaller in size permanently.

The average age that boys reach Stage 5 is about 16, although, as with Stages 1 to 4, there will be boys who enter Stage 5 when they are younger and some when they are older.

The pubic hair is also fairly well developed by Stage 5, but pubic hair may continue to grow until the boy reaches the age of 20.

Some boys have quite a bit of pubic hair; others have very little. How much you have will probably depend on your family. If the men in your family have lots of hair, you probably will too. If the men in your family are not especially hairy, the chances are that you will not be either. Again, this is not a hard and fast rule, but boys often take after their fathers in this way.

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