The Ultimate PCOS Handbook: Lose weight, boost fertility, clear skin and restore self-esteem. Theresa Cheung

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       CHAPTER 3 PCOSANDYOUR LIFE STAGES – FROM PUBERTY TO MENOPAUSE

      It’s clear that there can be different stages of PCOS throughout your life. Studies¹ show, for instance, that younger women tend to have substantial difficulties with their periods, whereas older women² tend to have other problems such as diabetes and hypertension (high blood pressure).

      PCOS symptoms often appear first during puberty, though – as mentioned in Chapter 2 – recent research suggests that PCOS may begin even earlier. According to lead author David Abbott, Ph.D., of the Wisconsin National Primate Center at the University of Wisconsin-Madison,³ PCOS develops in the first and second trimesters of pregnancy when excess androgens are present.

      But for now, here’s what we know about how PCOS affects your hormonal life stages, from puberty to menopause and beyond.

      PUBERTY AND PCOS

      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 СКАЧАТЬ