Whilst the likelihood of pregnancy is less in the mature woman, it is important to remember that as long as there is menstruation, the possibility of pregnancy exists.
THERE is a natural decline in fertility with increasing age, especially from the late 30s. However, ovulation can occur right up to the menopause.
It has been reported that 93% of women aged 40 to 55 years with regular cycles appear to ovulate each cycle.
The risks of chromosomal abnormalities, miscarriage, pregnancy complications, and maternal illness and death increase in women aged 40 years or more.
Notwithstanding the decline in fertility, effective contraception is necessary to prevent an unintended pregnancy. It is pertinent to note that the user failure rates of all contraceptive methods are less after 35 years of age.
Menopause, which occurs when ovarian function fails, is reached if a woman has not had a period for 12 consecutive months. This is a retrospective diagnosis. The average age of the menopause is 50 to 51 years.
There is no contraceptive method that cannot be used in women aged 40 years and above. When prescribing contraception for the mature woman, doctors take into consideration medical, behavioural and social factors as well as the features of the various contraceptive methods.
Combined oral contraceptive
The combined oral contraceptive (COC) is suitable for women above 35 years who do not smoke and who do not have a family history of cardiovascular disease, diabetes, and hypertension.
COC may reduce menstrual pain (dysmenorrhoea) and bleeding. Its use in the perimenopause may help in the maintenance of bone density (BMD) and help reduce the risk of osteoporosis, which is related to fracture risk.
COC provides protection against ovarian and endometrial cancer. This protection continues for 15 years or more after its use is discontinued. There is also a reduction in the risk of colorectal cancer with COC use.
COC use may lead to a reduction in the incidence of non-cancerous (benign) disease of the breasts and menopausal symptoms.
There is a slight increase in the relative risk of breast cancer in all current users of COC. As the incidence of breast cancer increases with age, this risk will become more significant in those above 40 years. This is reduced to “no risk” 10 years after stopping COC.
Smokers aged 35 years and above would be advised that the risks of COC outweigh the benefits. Women suffering from migraine with aura, cardiovascular disease or stroke would be advised not to use COC.
There is a very small increased risk of stroke with COC use. Hypertension may also increase the risk of stroke and heart attack (myocardial infarction) in COC users. That is why blood pressure is checked before and at least six months after commencement of COC in those aged 40 years or more, and at least annually after that.
It is usual practice to prescribe a low dose (less than 30mcg ethinyl oestradiol) COC to women aged 40 years and above.
Progestogen only Pill
Progestogen-only pills (POP) are as effective as COC in women aged 40 years and above. Altered bleeding patterns are common with POP. As absent periods (amenorrhoea) occur in POP users, it cannot be assumed that when it occurs, it is due to POP. Pregnancy and menopause have to be excluded when amenorrhoea occurs.
The levonorgestrel-releasing intrauterine system (LNG-IUS) is used in the treatment of heavy periods after uterine pathology has been excluded.
POP may reduce dysmenorrhoea. It does not appear to increase the risk of myocardial infarction, stroke or venous thromboembolism.
There is no conclusive evidence of an association between progestogen-only methods and breast cancer.
There is a small loss of BMD associated with progestogen-only injections. This usually recovers upon discontinuation of the injections.
Depot medroxyprogesterone acetate (DMPA) is usually not prescribed to women with cardiovascular risk factors because progestogens affect blood lipids. DMPA is not recommended for women aged 50 years or more.
The return to fertility can be delayed for up to one year after the discontinuation of progestogen only injections.
Intra-uterine contraceptive device
Users of the copper intra-uterine contraceptive device (IUCD) could have abnormal uterine bleeding, ie spotting, heavy or prolonged periods, which is common in the initial three to six months after insertion.
The LNG-IUS has advantages in the mature woman who is still menstruating. Not only does it provide contraception, it also reduces or eliminates heavy menstrual flow, which occurs in 5% of women aged 30 to 49 years.
Barrier contraceptives and spermicides are also suitable for the mature woman.
When used correctly and consistently, male and female condoms are effective at preventing pregnancy up to 98% and 95% respectively.
The effectiveness of diaphragms and caps, when used correctly and consistently with spermicides at preventing pregnancy, is between 92% and 96%.
If lubricants are used, it is important to remember to use non-oil-based ones with latex condoms.
Male and female sterilisation are also suitable for the mature couple. It is pertinent to note that the effectiveness of long acting reversible contraception – COC, POP and IUCD – can be as effective as sterilisation.
The different emergency contraception methods, ie levonorgestrel, ulipristal acetate, Yuzpe regime and IUCD are also suitable for the mature woman.
Fertility awareness methods are more difficult to initiate and adhere to when there are irregular menstrual cycles, which is common in women in their 40s and early 50s.
Condom use can reduce the acquisition and transmission of sexually transmitted infections. This method is recommended for women who have multiple sexual partners or who are unsure about the status of their sexual partner.
When to stop contraception is a common question that mature women ask their doctors. An informed discussion with the doctor would be helpful.
Users of hormonal contraception, ie COC and POP, should remember that amenorrhoea is not a reliable indicator of ovarian failure. The measurement of follicle stimulating hormone (FSH) may be used to diagnose menopause.
The use of FSH measurements is usually limited to women more than 50 years old or those using POP. FSH is not a reliable indicator of the menopause in COC users even if the measurement is done at a time when no hormones are taken.
It is generally accepted that women who are using non-hormonal contraception (copper IUCDs, barrier contraceptives) should continue using it for two years after the last menstrual period for those below 50 years of age.
It is also generally accepted that contraception should be continued for one year after the last menstrual period for those aged 50 years old or more.
Copper IUCDs inserted at or above 40 years of age can be used until the menopause or when contraception is not required any more.
LNG-IUS inserted at or above 45 years can use it until the menopause. The manufacturer recommends that it be changed no later than five years after insertion.
All types of IUCDs should be removed after the menopause is reached or when contraception is no longer required.
Hormone replacement and contraception
Hormone replacement formulations are not contraceptives and cannot be relied on for contraception.
Many women commence hormone replacement (HRT) before they reach the menopause. In such situations, it is difficult to know when the menopause occurs and how long contraception is needed.
Stopping the hormone replacement pills for six to eight weeks and then checking the FSH levels can confirm the menopause.
A POP can be used with HRT to provide effective contraception provided the HRT contains progestogen and oestrogen.
The LNG-IUS can be used with women on oestrogen-only HRT to provide endometrial protection. It has to be changed no later than five years after insertion irrespective of the user’s age at the time of insertion.
There is a variety of contraceptive methods that can be used by the mature woman. Whilst the likelihood of pregnancy is less in the mature woman, it is important to remember that as long as there is menstruation, the possibility of pregnancy exists. Effective contraception is necessary to avoid an unintended pregnancy.
Dr Milton Lum is a member of the board of Medical Defence Malaysia. This article is not intended to replace, dictate or define evaluation by a qualified doctor. The views expressed do not represent that of any organisation the writer is associated with. For further information, e-mail firstname.lastname@example.org. The information provided is for educational and communication purposes only and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
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