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Family Doctor Books
Preview of Understanding Hysterectomy

The uterus, referred to since Biblical times as the ‘womb’, is a very remarkable organ, capable of expanding to contain a full-grown baby and of shed- ding its lining up to 500 times during your life at the time of your monthly period. The resultant stresses and strains on its supporting structures during pregnancies and the repeated shedding and re-growth of its lining may lead to problems such as prolapse or heavy menstrual bleeding. This chapter describes what the normal uterus and its related structures look like and how they work, and summarises what may go wrong.

When you’re not pregnant, your uterus is approximately pear-sized. It has a thick muscular wall and a central cavity with a lining that is richly supplied with blood vessels. This lining is known as the endometrium and it provides nourishment for the embryo during the very early days of life. Otherwise, the lining of the uterus is shed each month, resulting in a flow of blood lasting for several days. This is known as the menstrual flow, menstruation or the monthly period. The uterine muscle wall expands greatly during pregnancy and strong contractions of this muscle wall during childbirth give rise to the pains of labour. You experience similar contractions on a much smaller scale during menstruation, and this is the cause of the period pain (dysmenorrhoea) which troubles so many women.

The uterus sits centrally in the pelvis, supported by strong fibrous structures called ligaments.

The cervix

  • The cervix (or neck of the uterus) is the link between the uterus and the vagina (or birth canal) and is found at the top of the vagina. It is a firm, smooth, rounded structure with a central opening which:
  • dilates (opens up) during labour
  • allows menstrual blood to flow through it during your periods
  • allows sperm to travel through it into your uterus during sexual intercourse.
When a doctor needs to look at your cervix, this can easily be done by inserting an instrument called a speculum into your vagina, and most women are used to having this done when their doctor performs routine smear tests.

The fallopian tubes and ovaries

The ovaries are situated on either side of the pelvis and are white, slightly knobbly and grape-sized. They are extremely important because they are the source of eggs and also of the hormones, oestrogen and progesterone (see below), which control the menstrual cycle. Each month an egg is released from one of the two ovaries in turn by a process called ovulation. This occurs at around day 14 of the menstrual cycle. The egg then enters the adjoining fallopian tube, one of two long, delicate structures attached to the uterus. This is where the egg may meet up with sperm if you have had sexual intercourse, so beginning a pregnancy. A woman is born with a full supply of immature eggs and, from puberty onwards, these eggs gradually mature so that one is released each month until the egg supply finally runs out at the time of the menopause (see below).

The ovaries are situated at either side of the uterus, connected to it by the fallopian tubes.

Supporting Structures

The uterus and cervix sit centrally in the pelvis, at the top of the vagina, supported by strong fibrous structures called ligaments. These ligaments are attached in turn to the bones of the pelvis. They are sufficiently elastic to allow them to stretch considerably during pregnancy and then return to their former size afterwards. In some women, particularly those who are past the menopause and those who have had children, this elasticity is reduced and the ligaments are weakened, leading to prolapse, or descent, of the uterus and cervix. This causes discomfort, a dragging sensation and an awareness of a swelling or bulge at the vaginal opening.

In front of the vagina and close to the cervix is the bladder, which stores then gets rid of urine through a short narrow passageway called the urethra. Behind the vagina is the rectum (back passage) where the bowel expels faeces. These organs are supported by ligaments and muscles that stretch during pregnancy and childbirth. The ligaments and muscles that support the uterus, bladder and rectum, together with the walls of the vagina, are referred to as the ‘pelvic floor’. When you’re pregnant, you’re taught how to exercise the muscles of your pelvic floor and improve their strength once you’ve had your baby. Women who have a pelvic operation will need to do the exercises too as they help to prevent any weakness developing and so keep the bowels and bladder working properly.

Female internal anatomy of the lower abdomen.

The menstrual cycle

For around 40 years (on average, between the ages of 12 and 52), you experience monthly menstrual bleeding from the uterine lining, except for those times when you may be pregnant or breast-feeding. The average length of the menstrual cycle is 28 days but it is quite normal for it to vary between 24 and 35 days and occasionally longer. Some women find that the bleed-ing is accompanied or preceded by crampy pain (dysmenorrhoea or period pain), caused by uterine contractions. It may also be preceded by mood changes, bloating and breast tenderness, now referred to as the premenstrual syndrome (PMS) and formerly called premenstrual tension (PMT). These symptoms are caused by the hormones produced in the ovaries, which act mainly on the uterus but also have effects elsewhere in the body. Different societies vary in their views about menstruation and, within all societies, individual women have vastly different experiences of their monthly periods. However, most look on menstruation as an unwelcome, albeit necessary, process.

Female hormones

Oestrogen is the main female hormone produced by the ovaries and is responsible for the thickening of the uterine lining during the menstrual cycle. It also affects the vagina, breasts, bones and other tissues (for example, walls of blood vessels).
Progesterone, the other female hormone, is produced only after the egg is released at ovulation and acts on the lining of the uterus, thickening it in preparation for a possible pregnancy. If you don’t conceive that month, your hormone levels fall and your period starts.

The production of hormones and release of eggs from the ovaries are controlled by a small gland in the brain, called the pituitary gland, which regulates the length of the menstrual cycle.

HOW OESTROGEN AFFECTS THE BODY
Vagina


Breasts



Bones




Other tissues		 Moistens and lubricates
Protects against infection

Involved in breast development
Causes activity in the glands of the breast (Causes cyclical swelling and discomfort in some women)

Important for bone development
Protects against loss of bone mineral
Helps to preserve bone strength

Keeps arterial walls healthy

Protects against heart disease

The menopause

The menopause is the last menstrual period experienced by a woman. It occurs, at an average age of 52 in most Western countries. It happens when the supply of eggs in the ovaries eventually runs out. It may be sudden or gradual; some women experience increasing irregularity of their periods for months or even years in the lead-up to the menopause. As your supply of eggs declines, your hormone levels start to fall and this is what may cause the symptoms of hot flushes, night sweats, vaginal dryness and mood fluctuations that trouble many women. For most women, these symptoms are transient but a few find that they are a serious problem for quite a long time.

If this happens to you, your doctor may suggest treating the symptoms with hormone replacement therapy (HRT) and you may want to consider it even if the menopause doesn’t affect you badly. This is because HRT may also have an important role in disease prevention: when your body stops producing the hormone oestrogen, you begin to lose calcium and minerals from your bones, and you also face an increased risk of developing heart disease. In addition, you may be predisposed to other health problems. These increased risks don’t affect everyone after the menopause, but having your ovaries surgically removed at the time of hysterectomy is likely to aggravate these problems and this issue is discussed later in the book.

Common disorders of the uterus

Given the total number of menstrual cycles experienced by most women, it is not surprising that menstrual problems are common. These comprise painful periods, heavy periods, irregular bleeding and the premenstrual syndrome (PMS). Uterine fibroids are common benign tumours that may be a cause of heavy periods. Many women experience menstrual problems at some time in their lives but often these are temporary and settle down on their own or with simple treatment. Bleeding problems are particularly common in the lead-up to the menopause. Excessive bleeding is not only inconvenient, uncomfortable and embarrassing, it may also lead to anaemia (shortage of iron caused by blood loss).

Even after the menopause, the problems are not all over because this is the time when many women experience problems with prolapse of the uterus or vaginal walls. In particular, older women are more at risk of development of cancer of the uterine lining or ovaries, although fortunately these conditions are not common.
Hysterectomy is commonly recommended for menstrual problems and may be part of the treatment for many other gynaecological disorders. The most important of these are outlined below, and you will find more details on several of them in later chapters.

Heavy menstrual periods

Investigation may identify no serious cause for heavy periods and the problem is put down to a disorder of the shedding and re-growth of the uterine lining – so-called dysfunctional uterine bleeding. Menstruation is a very complex process and one that is not yet fully understood. It is likely that repeated menstrual cycles lead to disorders in this process because periods tend to get heavier as women get older. Another factor may be that some women become very intolerant of their periods once they have completed their families and are less prepared to put up with the monthly inconvenience. In some cases, the problem is related to changes in the levels of hormones produced by the ovaries in the lead-up to the menopause. More specifically, some women stop producing progesterone although their ovaries still release oestrogen. This means that there is not enough progesterone to counteract the build-up of the uterine lining which is caused by oestrogen. This leads to heavy, irregular or frequent bleeding.

In the absence of an obvious cause for the bleeding, decisions about treatment must depend largely on the severity of the symptoms, the impact they are having on the lifestyle and commitments of an individual woman, and whether heavy bleeding has led to anaemia. You should always be offered medical treatment in the first instance and it often works. Endometrial ablation can also be helpful if you have dysfunctional uterine bleeding.

If these measures fail, removal of the uterus, albeit rather drastic, will guarantee permanent relief but, as major surgery is involved, the risks as well as the benefits must always be fully considered).

Uterine fibroids

Fibroids are rounded swellings of various sizes, composed of muscle and fibrous tissue, which grow in the wall of the uterus. They are extremely common and do not always cause symptoms, but, if they distort the cavity of the uterus, they may be a cause of heavy bleeding. Heavy periods caused by fibroids may be treated medically (see page 28), but this is less successful if the fibroids are numerous or large because medical treatments will not permanently shrink the fibroids. Similarly, endometrial ablation may not be possible or is less likely to succeed if there are large fibroids. Fibroids can be removed individually without removing the whole uterus, but this type of operation, known as myomectomy, is usually offered only to women who may want to have children in future. However, if you have completed your family and are troubled by symptoms such as heavy bleeding or pelvic pressure, hysterectomy will bring a much welcomed relief.

Menstrual pain

Only rarely is hysterectomy recommended for relief of menstrual pain because in most cases it responds to simple medical treatments, such as pain-killers or the oral contraceptive pill. Severe pain associated with menstruation, which is not relieved by standard medical treatments, may be caused by endometriosis (see below ). Another condition, more common in older women who have had children, is ‘pelvic congestion syndrome’ in which periods are both painful and heavy with a build-up of pain, including backache and painful intercourse, in the lead-up to the period. Similar symptoms are caused by adenomyosis but this condition is difficult to diagnose. Hormonal therapies including the ‘pill’ can be successful by blocking ovulation and the hormone changes that follow because these may trigger pelvic pain in some women. Hormones can also be used to stop the menstrual cycle altogether. If this is not successful, hysterectomy is a possible option. Some women with symptoms of pelvic congestion have underly- ing problems such as stress or a depressive illness which may be aggravating the menstrual problem. It is important to appreciate that, if your pelvic pain is not related to the menstrual cycle, it is not likely to improve after a hysterectomy.

Severe or persistent endometriosis

Endometriosis arises because some women shed a little of the lining of their womb through their fallopian tubes in to the pelvis during menstruation. If this uterine lining tissue remains on the ligaments behind the uterus or on the ovaries, it may respond to the hormone changes of the menstrual cycle, giving rise to additional pain before or during menstruation. It may also cause deep discomfort or pain during intercourse. Even if endometriosis symptoms are improved with medical treatment, the condition tends to recur and removal of the ovaries, together with hysterectomy, is a possible long-term solution.

In cases of severe endometriosis, there may be adhesions (scar tissue) in the pelvis, causing the uterus and ovaries to stick to other structures, such as the bowel and bladder, making a hysterectomy potentially difficult. When this happens, it is neces- sary to remove the ovaries as well because the condition is depend-ent on natural hormone produc-tion. Severe endometriosis may be a cause of infertility and this may make the decision to have a hysterectomy difficult for those women who are hoping to have one or more children in the future. In this situation, it is particularly important that all alternative options are fully considered.

Although endometriosis is hormone dependent, most women can take HRT if they lose their ovaries. However, it may be necessary to give progesterone together with the oestrogen to prevent the oestrogen stimulating any remaining endometriotic tissue, if there is concern that the endometriosis has not been completely removed.

Endometriosis may cause the ovaries and uterus to stick to other structures, making hysterectomy potentially difficult.

Adenomyosis

This condition causes heavy and painful periods as a result of the presence of uterine lining tissue in the uterine wall, causing the uterus to be tender and bulky. In contrast to endometriosis, which is more common in women who have not had children, adenomyosis usually occurs in women who have had several pregnancies. It may develop as a complication of endometrial ablation. It can be treated medically but hysterectomy may be recommended if medical treatments are not successful. The diagnosis of adenomyosis is dif-ficult to make on the basis of standard investigations because it is not visible on hysteroscopy or ultrasound scanning, and cannot be detected on an endometrial biopsy. Most cases are discovered only after a hysterectomy has been performed and the uterus examined by a pathologist.

Uterine prolapse

A uterine prolapse is the descent of the uterus and cervix so that they no longer sit up at the top of the vagina, but can be felt lower down, sometimes as far down as the vaginal opening. Prolapse of the uterus is caused by weakness of its supporting structures, usually as a consequence of child-bearing. You are most likely to develop it after rather than before the menopause and it is usually accompanied by prolapse of the vaginal walls. When it happens, you experience a dragging sensation and you and/or your doctor may feel a smooth swelling at the vaginal opening. Some women tolerate a prolapse for many years and come to no harm, but it can be a considerable nuisance and restrict your activities unnecessarily. If it is very large, the skin over the prolapse may become irritated by contact with underclothing, leading to discharge and even bleeding.

Minor degrees of prolapse may not require an operation or may be treated by a pelvic floor repair which leaves the uterus intact. However, removal of the uterus through the vagina (vaginal hysterectomy) together with repair of the pelvic floor is usually recommended if the prolapse is large. When a woman develops a prolapse before she has had all the children she would like, she will usually be advised to delay having surgical treatment until her family is complete. A ring pessary can be fitted as a temporary measure to support the pelvic floor. Ring pessaries are also suitable for the treatment of women who are not well enough to undergo an operation.

Uterine prolapse is the descent of the uterus and cervix through the vagina.

Ovarian cysts and tumours

An ovarian cyst is a collection of fluid within the ovary. Small cysts commonly develop as a complication of the menstrual cycle and normally do not require any treatment because they go away on their own. Larger cysts can be drained or removed without removing the ovary. If the ultrasound scan shows that the cyst is made up of solid areas as well as fluid, or if there is a solid swelling on the ovary (an ovarian tumour), it may be necessary to remove the whole ovary. If the cyst or tumour is very large or if there is doubt about its nature, your gynaecologist may recommend removal of the uterus and the other ovary, provided that you do not wish to have any more children. This is especially likely if there is concern that the cyst may be malignant (cancerous). Although most ovarian cysts are benign, there is a greater risk of cancerous changes if it is very large. Scans and blood tests are helpful in predicting whether an ovarian cyst is malignant. There is also a small risk that a similar cyst may develop at a later stage in the other ovary. More information is given about the treatment of ovarian cancer in a later chapter.

Ovarian cysts.

Premenstrual syndrome

Hysterectomy is sometimes recommended for women with severe premenstrual mood swings (premenstrual syndrome or PMS). However, this is unlikely to help unless you also have significant problems with heavy bleeding or menstrual pain. Some women with very severe PMS benefit from removal of their ovaries, but this is a very drastic measure and does not guarantee a cure. Long-term treatment with hormone replacement therapy (HRT) is essential for women who lose their ovaries at a young age. As this is given continuously and at a low dose, it is unlikely to lead to a recurrence of the PMS symptoms, although some women with PMS are unusually sensitive to the effects of hormones and have difficulty with HRT.

Who needs a hysterectomy?

Most hysterectomies are done to relieve menstrual problems, particularly bleeding problems. Some of these will be the result of specific gynaecological disorders, most commonly fibroids. In many cases no specific cause can be found but simpler forms of therapy have failed to provide sufficient relief. Hysterectomy is rarely the only available solution for a menstrual problem but it is carried out with increasing frequency because of its success. Nevertheless, research has shown that the number of hysterectomies done for this reason varies greatly in different parts of the country and that this reflects differences of opinion among doctors. Thus the range of treatments you are offered may differ depending on where you live. In older women, most hysterectomies are done to treat uterine prolapse or as part of the treatment for certain forms of cancer. The subject of hysterectomy for cancer is discussed in the chapter starting on page 36.
 
KEY POINTS
  • The menstrual cycle is controlled by the hormones oestrogen and progesterone, produced by the ovaries
  • A woman sheds her uterine lining each month during menstruation – up to 500 times in her lifetime
  • Common problems include heavy bleeding, menstrual pain, mood swings (PMS), fibroids, endometriosis and prolapse of the uterus
  • Bleeding disorders are especially common near the menopause because of changes in hormone production by the ovaries