Menopause is a retrospective diagnosis, made after a woman has had no periods for 12 months. It is defined as a permanent end to menstruation. On average, women experience the menopause around the age of 51 years, although this can vary significantly. Menopause is a normal process affecting all women reaching a suitable age.
Menopause is the point at which menstruation stops.
Postmenopause describes the period from 12 months after the final menstrual period onwards.
Perimenopause refers to the time around the menopause, where the woman may be experiencing vasomotor symptoms and irregular periods. Perimenopause includes the time leading up to the last menstrual period, and the 12 months afterwards. This is typically in women older than 45 years.
Premature menopause is menopause before the age of 40 years. It is the result of premature ovarian insufficiency.
Menopause is caused by a lack of ovarian follicular function, resulting in changes in the sex hormones associated with the menstrual cycle:
- Oestrogen and progesterone levels are low
- LH and FSH levels are high, in response to an absence of negative feedback from oestrogen
Inside the ovaries, the process of primordial follicles maturing into primary and secondary follicles is always occurring, independent of the menstrual cycle. At the start of the menstrual cycle, FSH stimulates further development of the secondary follicles. As the follicles grow, the granulosa cells that surround them secrete increasing amounts of oestrogen.
The process of the menopause begins with a decline in the development of the ovarian follicles. Without the growth of follicles, there is reduced production of oestrogen. Oestrogen has a negative feedback effect on the pituitary gland, suppressing the quantity of LH and FSH produced. As the level of oestrogen falls in the perimenopausal period, there is an absence of negative feedback on the pituitary gland, and increasing levels of LH and FSH.
The failing follicular development means ovulation does not occur (anovulation), resulting in irregular menstrual cycles. Without oestrogen, the endometrium does not develop, leading to a lack of menstruation (amenorrhoea). Lower levels of oestrogen also cause the perimenopausal symptoms.
A lack of oestrogen in the perimenopausal period leads to symptoms of:
- Hot flushes
- Emotional lability or low mood
- Premenstrual syndrome
- Irregular periods
- Joint pains
- Heavier or lighter periods
- Vaginal dryness and atrophy
- Reduced libido
A lack of oestrogen increases the risk of certain conditions:
- Cardiovascular disease and stroke
- Pelvic organ prolapse
- Urinary incontinence
A diagnosis of perimenopause and menopause can be made in women over 45 years with typical symptoms, without performing any investigations.
NICE guidelines (2015) recommend considering an FSH blood test to help with the diagnosis in:
- Women under 40 years with suspected premature menopause
- Women aged 40 – 45 years with menopausal symptoms or a change in the menstrual cycle
Fertility gradually declines after 40 years of age. However, women should still consider themselves fertile. Pregnancy after 40 is associated with increased risks and complications. Women need to use effective contraception for:
- Two years after the last menstrual period in women under 50
- One year after the last menstrual period in women over 50
Hormonal contraceptives do not affect the menopause, when it occurs or how long it lasts, although they may suppress and mask the symptoms. This can make diagnosing menopause in women on hormonal contraception more difficult.
Good contraceptive options (UKMEC 1, meaning no restrictions) for women approaching the menopause are:
- Barrier methods
- Mirena or copper coil
- Progesterone only pill
- Progesterone implant
- Progesterone depot injection (under 45 years)
The combined oral contraceptive pill is UKMEC 2 (the advantages generally outweigh the risks) after aged 40, and can be used up to age 50 years if there are no other contraindications. Consider combined oral contraceptive pills containing norethisterone or levonorgestrel in women over 40, due to the relatively lower risk of venous thromboembolism compared with other options.
TOM TIP: It is worth making a note and remembering two key side effects of the progesterone depot injection (e.g. Depo-Provera): weight gain and reduced bone mineral density (osteoporosis). These side effects are unique to the depot and do not occur with other forms of contraception. Reduced bone mineral density makes the depot unsuitable for women over 45 years.
Management of Perimenopausal Symptoms
Vasomotor symptoms are likely to resolve after 2 – 5 years without any treatment. Management of symptoms depends on the severity, personal circumstances and response to treatment. Options include:
- No treatment
- Hormone replacement therapy (HRT)
- Tibolone, a synthetic steroid hormone that acts as continuous combined HRT (only after 12 months of amenorrhoea)
- Clonidine, which act as agonists of alpha-adrenergic and imidazoline receptors
- Cognitive behavioural therapy (CBT)
- SSRI antidepressants, such as fluoxetine or citalopram
- Testosterone can be used to treat reduced libido (usually as a gel or cream)
- Vaginal oestrogen cream or tablets, to help with vaginal dryness and atrophy (can be used alongside systemic HRT)
- Vaginal moisturisers, such as Sylk, Replens and YES
Last updated June 2020