Almost every tissue in the body has estrogen receptors, which suggests that estrogen has a role to play in their function. This is true of the genitourinary system, which includes the external genitalia, vagina, bladder and urethra. The loss of estrogen which comes with menopause has several effects on these tissues which, used to come under terms such as atrophic vaginitis, vulvovaginal atrophy, and various urinary conditions including urinary incontinence. More recently, the term Genitourinary Syndrome of Menopause (GSM) is used to refer to these issues as a group.
Dr Riordan is a Fellow of the Royal College of Surgeons, England. She spent several years as a fertility specialist at both Sims and ReproMed IVF clinics. She is a member of the Urology team at St Michael’s Hospital, Dun Laoghaire and a Surgeon Prosector in the anatomy department of the RCSI.
“Genitourinary syndrome of menopause (GSM) is a more accurate and inclusive term that describes the multiple changes occurring in the external genitalia, pelvic floor tissues, bladder and urethra, and the sexual sequelae of loss of sexual function and libido, caused by hypoestrogenism during the menopause transition and post menopause. These genitourinary changes primarily occur in response to reduced estrogen levels and aging, and do not settle with time”. (Kim et.al, 2015)
There are two main types of incontinence; stress urinary incontinence (SUI) and urge urinary incontinence (UUI). Aging is a large factor in the development of urinary incontinence, but menopause can have an added impact. By the age of 70, 1 in 2 women has a degree of urinary incontinence and it has an enormous impact on quality of life.
SUI is leakage of urine when the pressure on the bladder is increased from within the abdomen, as happens when the abdominal muscles are tightened during coughing, laughing, sneezing or lifting something heavy. It can also happen when there is extra pressure applied to the pelvic floor while running, or classically, jumping on a trampoline – a major no-no for many mothers! Having a baby increases the chance of having SUI from 1 in 10 to 1 in 3.
UUI is leakage which happens when you have the sudden urge to pee and can’t quite hold on until you get to the toilet. It is less common than SUI, affecting approx 1 in 30 women, but becomes more common with age and with the onset of menopause. It is caused by overactivity of the muscle of the bladder wall, also known as overactive bladder syndrome (OAB) and is associated with reduced bladder capacity, urinary frequency, urgency and the need to get up multiple times at night to pass urine. You may have OAB without leakage.
The bony pelvis is like a bowl without a bottom, into the top of which rest the abdominal contents. The pelvis itself contains the bladder, uterus and rectum, all of which would fall out through the bottom of the bowl were it not for a muscular sheet or diaphragm stretched across it. This group of muscles is collectively referred to as the pelvic floor. It contains condensations of muscle fibres around the bladder neck and a sling around the lower rectum which act as sphincters to prevent unwanted escape of their contents. When you are about to cough or sneeze etc, there is a reflex tightening of the pelvic floor muscles a split second beforehand, so that when the cough occurs, everything is sealed tight and no urine or faeces are squeezed out. If the pelvic floor is weak, this may not happen strongly or quickly enough and leakage occurs. If the pelvic floor is significantly weak, over time the pelvic organs, ie the bladder, uterus and rectum, may slip downwards and bulge through it in the form of a prolapse. If the bladder bulges through the pelvic floor, this is known as a cystocele.
There are many factors that can weaken the pelvic floor, such as a chronic cough or excess intra abdominal fat. Women are at higher risk than men because of their childbearing potential. Firstly, the birth canal passes through the pelvic floor which necessitates a third opening and thus a further potential weakness. Secondly, the pelvic floor is subjected to stretching during pregnancy and childbirth. Even carrying a baby for 9 months puts pressure on the pelvic floor and will stretch it. Pushing a baby through it during vaginal delivery, particularly if the passage is rapid or if instruments are required, stretches it even more dramatically. Indeed, the muscles can tear. Not only are the muscle fibres stretched, but the elastic and collagen fibres are also stretched or broken. The result is a loss of muscle tone and strength of the pelvic floor as a whole. Pelvic floor exercises are extremely important in the post delivery phase, to restore as much muscle tone as possible, but the pelvic floor will never be as taught as before pregnancy. Awareness and exercise of the pelvic floor before pregnancy is very beneficial in terms of minimising any damage during pregnancy and childbirth.
As we get older, our muscle tone in general will tend to reduce. A sedentary lifestyle or reduced participation in exercise contributes to this loss of muscle tone. With menopause, when estrogen levels fall, this reduction accelerates because low estrogen leads to loss of muscle tone and strength, including that of the pelvic floor muscles. A fall in estrogen results in a loss of collagen of up to 30% in the first 5 years of menopause. On top of that, with aging, our metabolism slows and lower estrogen levels make women prone to gaining weight and to store any extra fat around their abdomen. This additional abdominal fat adds to the pressure on their pelvic floor. As a result, women who previously had things under control, may find that leakage now becomes a problem.
Another factor is the atrophy of the vaginal and urethral epithelium, which comes with a decline in estrogen. From a continence point of view, if the urethral lining is less puffy, it is less able to hold in any urine which may try to escape. The cells of the urethra and the trigone of the bladder may become more sensitive, leading to increased irritability, urinary frequency and discomfort. Finally, the loss of glycogen-rich vaginal secretions leads to a decline in the Lactibacillus population in the vagina. This causes an increase in vaginal pH, a disruption of the previously healthy and stable vaginal microbiome, and an increased propensity to population with pathogenic bacteria such as E.Coli. With menopause, may women find themselves prone to recurrent urinary tract infections (UTI). Anyone with even slight SUI or UUI, may find it worsened in the presence of a UTI.
Types of pelvic organ prolapse
Treatment
The first thing to bear in mind is that most women are reluctant to bring up incontinence with their doctor, either because they think it is a normal part of aging and something to be put up with, or because they are embarrassed. Without direct questioning, the problem may not be revealed. Secondly, an accurate diagnosis is important. It can be very clear which type of incontinence someone has, but quite commonly, women have a combination of both SUI and UUI, known as Mixed Urinary Incontinence. It can sometimes be difficult to determine how much each contributes to the problem and, therefore, which is the best treatment option. In this case, a urodynamic study may be helpful.
SUI
Pelvic floor exercises (PFE) can achieve significant improvement in up to 75% of women with SUI and may well avoid the need for any further treatments. However, 1 in 2 women have difficulty identifying and contracting their pelvic floor as the contractions are internal and the effect unseen.
Assessment by a specialist pelvic floor physiotherapist can be invaluable, both to identify an individual’s particular muscle weakness and ensure the most appropriate exercises are done, using the correct technique. Some improvement may be seen within weeks, but maximal benefit may not be seen for up to 6 months. As with all muscle exercise, continued exercise is necessary to maintain the effect, of course. Physiotherapists may use tools such as biofeedback and electrostimulation for women who have difficulty in contracting their pelvic floor.
The avoidance of constipation is important, as any loading of the rectum will increase pressure on the bladder and straining to open the bowel further increases pressure on the pelvic floor. Stool softening agents and plenty of fluid intake is helpful. The use of a footstool to raise the knees above hip height relaxes the abdomen and pelvic floor and helps with defaecation. Weight loss is essential for those with increased abdominal fat. Many exercises such as those which are part of a pilates or yoga programme, can help to restore muscle tone. Vaginal pessaries may be useful for support of the bladder neck.
When conservative measures have failed, surgical options may be required. These procedures are generally only provided by urogynaecologists or urologists with a special interest in this field and referral to a general urologist may delay accessing the appropriate treatment. Procedures include the injection of bulking agents around the bladder neck, mid-urethral slings to elevate and support the bladder neck or colposuspension. It is important to rule out UUI as surgery for SUI may unmask or make UUI worse, so a urodynamic study may be required pre-operatively.
UUI
Vaginal estrogen reverses the atrophy of the vaginal and urethral epithelium, making them thicker, less sensitive and reducing the incidence of UTI. It may also reduce the sensitivity of the bladder itself, thus reducing overactivity of the muscle. There is minimal systemic absorption of vaginal estrogen, with an initial peak, then almost no further absorption. Hence, it is perfectly safe for the vast majority of women to use and, indeed, is now to become available over the counter in the UK.
Pelvic floor physiotherapy is useful for both rehabilitation of the pelvic floor and retraining of the bladder to hold larger amounts of urine.
As with SUI, weight loss and avoidance of constipation is beneficial.
Bladder irritants such as fizzy drinks, caffeine and alcohol are best avoided. Although most people with OAB tend to instinctively restrict their fluid intake, this can be counter productive as concentrated urine is an irritant to the bladder and increases the risk of UTI.
Good diabetic control is vital as glucosuria is a bladder irritant and increases the risk of UTI. Over time, high blood glucose may also lead to neuropathy and a neurogenic bladder.
The addition of an anticholinergic or beta-3 adrenergic agonist may be required. If conservative treatment has failed, other options again require referral to a urogynaecologist or a urologist with a special interest. Treatments include intravesical Botulinum toxin (Botox) injections, percutaneous tibial nerve stimulation or sacral nerve stimulator implants.
It is important to bear in mind that rapid onset of symptoms of bladder irritation, particularly in older women or those with a history of smoking and also the presence of haematuria, may signify a bladder neoplasm and such symptoms should be carefully monitored. Lack of response to conservative management, should trigger referral to a urologist for possible cystoscopy.
Although SUI and UUI are the main types of urinary incontinence, one can also have overflow incontinence. This can be caused by obstruction which prevents the bladder emptying adequately, such as happens in men with enlarged prostates. Symptoms may begin with issues similar to OAB but develop to include weak urinary flow or a dribble, small amounts of urine passed, a feeling of incomplete emptying, having to get up multiple times at night to pass urine, incontinence and recurrent UTIs. In women, a significant cystocele may result in kinking of the urethra, thereby causing an obstruction. Many women find that they can initiate a second void by shifting position on the toilet and it is important that they do try to empty completely, if possible. Another cause of overflow incontinence is a neurogenic bladder, as can happen with certain neurological conditions such as Parkinson’s or MS. Neuropathy can also be the result of poorly controlled diabetes. Treatment of overflow incontinence depends on the cause and may entail surgery to elevate the bladder neck, learning how to self-catheterise or using an indwelling urinary catheter.
Finally, functional incontinence occurs when an issue such as poor mobility means you can’t make it to the toilet in time or arthritis means you cannot undo your clothes quickly enough. This increases with age and is not a direct result of menopause. In this situation, products such as pads and absorbent underwear may be the best option. For some, an indwelling urinary catheter can be useful.
With all aspects of GSM, it is important for healthcare professionals to bring the subject up. Awareness among the general public is increasing, but women still tend to be reluctant to do it themselves. Once out in the open, treatment can be simple, rapid and life-changing.
