The Ultimate PCOS Handbook. Theresa Cheung
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Puberty is the beginning of a physical transformation towards fertility, which usually takes about four years to complete. Body shape, hormone levels and behaviour all begin to change in response to hormonal instructions. Breasts develop, pubic hair grows, bones strengthen and height and weight increase.
In women without PCOS, before the onset of puberty, the pituitary gland prompts the ovaries and adrenal glands to start producing larger amounts of the sex hormones oestrogen and androgen.
Oestrogens, often known as the ‘female’ hormones, control breast development and changes in the vagina and its excretions. Before the first menstrual period (called menarche), levels of oestrogen in the bloodstream begin to fluctuate widely. The womb lining (endometrium) is affected by these hormonal changes until a point is reached when it starts to grow.
Meanwhile androgens, often known as the ‘male’ hormones, control the growth of pubic hair under the arms and in the pubic area, stimulate growth and weight gain and speed up the maturation of the bones and an increase in muscle mass. But androgens mostly come to a teenage girl’s attention when they cause that common and unwanted effect of puberty – acne.
These physical changes may also be accompanied by emotional conflicts, some of which are hormonally triggered. Sudden, unpredictable mood swings in adolescents can be due to the surges in these hormones (think about any PMS or PCOS mood swings you get and it might take you back to your teens).
FIRST OVULATION
The first ovulation doesn’t occur until around six to nine months after a girl’s first period.
The mechanisms for initiating menstruation are present in a child’s brain and pituitary gland from birth, but something keeps them turned off until puberty. Many scientists believe this is weight, with a body-fat ratio of around 25 per cent being the trigger. It’s thought that the hormone leptin, produced by fat cells, must achieve a certain level in the blood in order for menstruation to occur, and that this level must be sustained for the menstrual cycle to be regular.
As body weight during puberty increases it’s thought that the hypothalamus triggers the release of gonadotrophin-releasing hormone (GnRH). It’s thought that the body fat ratio triggers the onset of menstruation, some time between the ages of 11 and 18.
GnRH then stimulates the pituitary to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH). As we’ve seen in Chapter 1, in sexually mature females FSH and LH act on the follicle to stimulate it to release oestrogens and trigger the maturing of the egg and its release (ovulation) in the middle of the cycle. Later, LH stimulates the empty follicle to develop into the corpus luteum, which secretes progesterone during the latter part of the menstrual cycle to prepare the body for a possible pregnancy.
Somehow the brain senses the body mass or fat mass, and only lets puberty start when a certain weight is reached, typically around 7 stone (100 lb), although this can vary considerably. This would explain why petite girls often get their periods later than heavier or taller ones. It would also explain why some women stop getting periods when they lose too much weight (think of gymnasts, or women with anorexia or even athletes in hard training). Although this theory has its problems, as some very thin women do menstruate, it does make sense that pregnancy shouldn’t occur until a body has enough fat stores to see it through successfully.
Research4 indicates that a healthy diet with a balance of fats, proteins and carbohydrates is important for the onset and continuation of menstruation, whether a woman has PCOS or not. In the 1830s women typically began menstruation at the age of 17, while today the average age is 13. This change is thought to be linked to improved nutrition, but some argue that it’s due to rising obesity levels and exposure to hormones in the environment and to food additives.
Once menstruation has started, a continual release of the hormone GnRH is essential to keep periods regular. Stress and sudden body weight changes can upset the release of this hormone and cause irregular or absent periods. Again, perhaps this is the body’s way of ensuring that pregnancy only occurs when a woman’s mind and body are ready to support it.
HOW PCOS AFFECTS PUBERTY
In general, many girls with PCOS have a puberty that is normal in every respect except when it comes to periods. Breast and hair development are normal, as is the increase in weight and height, but a normal menstrual cycle isn’t established. Periods are either absent or irregular. Apart from the irregular periods, other typical symptoms of PCOS may not be present.
Some other research5 has suggested that girls with premature puberty who develop pubic hair early (say before the age of 8) have many of the signs and symptoms of PCOS. Throughout puberty these girls produces excess testosterone and have irregular periods. So, premature puberty could be an early sign of PCOS.
Some adolescent girls experience many of the same symptoms as adults – especially irregular or absent periods, unwanted hair, weight gain and acne. In rare cases these symptoms can occur very rapidly. A young girl may gain 30 or so pounds in a few months, even though her diet has not changed, or she might notice more and more dark hair on her chin and upper lip.
IF YOU SUSPECT YOUR DAUGHTER MAY HAVE PCOS
Adolescence is a tough time for a girl regardless of whether she has PCOS or not. But for girls with PCOS, it can be even tougher. They can often feel isolated and confused. At an age when appearance seems to be everything, girls with PCOS lose a great deal of self-confidence when their symptoms start appearing. This is made worse because many girls feel they haven’t got anyone to talk or feel too embarrassed to seek help.
If you suspect your daughter might have PCOS, either because her symptoms are physically obvious or because you know her cycle is irregular, it’s very important that you find a doctor who knows about PCOS and can diagnose it.
Puberty may seem chaotic but it does follow an orderly process, and if events fall out of line questions should be asked. If there’s early hair growth, or no period 12 months after breast and pubic hair development, or excessive acne or abnormal hair growth, do make sure you seek help and advice. You should also consult your daughter’s doctor if six months after they start her periods are very frequent, excessive or far apart.
Do be aware that, even today with increased awareness of PCOS, some doctors pass off early signs as ‘typical’ teenage symptoms – hair growth, acne, mood swings are common to many teenagers, after all. If you’re concerned, seek a second or a third opinion – when a health-care provider takes the time to explain what PCOS is and offers treatment options, a young woman may feel relieved that at last there’s an explanation and treatment for her problems. And an early start with control measures can make a real difference to health, self-image and quality of life.
Many girls with PCOS tell us that talking with a counsellor about their concerns can be very helpful, as can joining a support group for girls who have PCOS. (See our recommended websites for great online links.)
Generally the tests for PCOS in teens are the same as those for women, as are the treatment options offered, such as the contraceptive pill and metformin. The lifestyle and self-help advice given in Part 2 of this book can be broadly applied to teens as well.
PCOS AND FERTILITY
Many women with PCOS are diagnosed in their twenties and thirties, but some aren’t diagnosed until they are in their forties. This is because it’s during this time a woman is most likely to want to conceive, and many women with PCOS aren’t diagnosed until they have trouble getting pregnant. (This is a concern, as PCOS is far more than a fertility issue and has long-term health effects.)
You’ll find plenty of information about boosting fertility in Part 2.
PCOS AND PREGNANCY
Despite fertility problems, 70 per cent of women with PCOS do conceive naturally. It might be logical