As menopause approaches, needs change: but contraception is still important for sexually active older women.

Between peak childbearing years and menopause, a woman's fertility gradually declines, reducing her risk of an unplanned pregnancy. Yet, a risk still exists.

Not only is contraception important for a sexually active older woman, since pregnancy late in life presents increased risks to her health and that of her fetus, but also careful consideration should be given to providing a contraceptive method that is appropriate to the changing needs of her body. Furthermore, sexually active older women and men--just like younger individuals--may need to protect themselves against sexually transmitted infections (STIs), including HIV. (See articles, pages 26 and 29.) Those at risk of infection should be counseled to use condoms consistently and correctly and to reduce the number of their sexual partners.

The need for contraception to prevent pregnancy ends only at menopause when menses permanently end, signaling that the ovaries are no longer producing eggs that could be fertilized. Menopause is considered to have occurred only after a woman has not menstruated for one year. However, for a period of about four years before menopause--during perimenopause--a woman's ovaries may intermittently produce eggs, and she may become pregnant if she remains sexually active and does not use contraception. Meanwhile, about 50 percent of a woman's reproductive life occurs between the time she has achieved her desired family size and the time she has reached menopause. During that extended period, a sexually active woman needs effective contraception. (1)

Patterns of contraceptive use differ throughout the world, but sexually active women older than 35 tend to be particularly likely not to use contraception. Some erroneously believe that they cannot become pregnant so late in life. Many women also abandon contraception as they approach menopause because they mistakenly believe that use of contraception--particularly hormonal methods--grows more risky with advancing age, even among healthy women. (2)

The consequences of abandoning contraception before menopause, however, may be serious if not life threatening. At this stage of a woman's reproductive life, the medical risks of pregnancy to both mother and child are greatest and include pregnancy-induced hypertension, hemorrhage, increased risk of maternal death, spontaneous abortion, premature delivery, fetal abnormalities, and fetal and infant death. An unplanned pregnancy late in life can be emotionally stressful and even socially undesirable in some settings. Women older than 35 years also are particularly likely to abort unplanned pregnancies and to suffer complications and death associated with abortion. (3)

SELECTING AN APPROPRIATE CONTRACEPTIVE

A number of factors must be considered when helping a woman approaching menopause to select an appropriate contraceptive. Her physical condition is unique in that she may be experiencing and seeking relief from menopausal-like symptoms, or may desire protection against bone loss and various reproductive tract cancers. (4) Her reproductive priorities and sexual behavior also may differ from those of a younger woman. She may be less concerned about preserving her fertility. Divorce, separation, or widowhood may have ended a stable relationship with one sexual partner, and she may now have new and even multiple sexual partners, putting her at increased risk for an STI. However, she is likely to have sex less frequently and, when she does have sex, she may anticipate the event and be better prepared to protect herself against both pregnancy and STIs. (See article, this page.) Her likelihood of becoming pregnant may be further reduced if her sexual partner is an older man. (5) Recent research involving 782 healthy European couples indicates that men's fertility begins to drop as early as age 35, resulting in delayed conception. (The study found, for example, that a 35-year-old woman with a 35-year-old partner had a 29 percent chance of getting pregnant in one month. But a 35-year-old woman with a 40-year-old partner had only an 18 percent chance of doing so.) (6)

Little is known about patterns of contraceptive use by older women, especially those in developing countries. But, in general, sterilization is the most common choice of older women and men. According to U.S. data from the 1995 National Survey of Family Growth, two-thirds of married 40- to 44-year-old men and women chose sterilization as a contraceptive method, compared with one-third of married 30- to 34-year-olds and 7 percent of married 20- to 24-year olds. (7) In a study in New Delhi, India, of the contraceptive use and sexual behavior of 500 women--half of whom were 35 years old or older--over 40 percent of the older women had been sterilized. In this setting, where it is common to marry and then bear children early in life, many older women apparently chose to be sterilized because they considered their reproductive careers to be over. Only 1.2 percent of older women used oral contraceptives (OCs), compared with 10 percent of younger women. And while both younger and older women preferred the use of an intrauterine device (IUD) over OC use, IUD use fell markedly from 23 percent to 5 percent after the age of 35. (8)

Female sterilization is a safe and highly effective irreversible form of contraception for healthy older women. Moreover, a growing body of evidence--including a large, prospective cohort study--suggests that it may reduce the risk of ovarian cancer. (9) "How this important protection might occur is unknown," says Dr. David Grimes, FHI vice president of biomedical affairs and author of a published editorial on the subject. (10) "Altered blood supply to the ovary is one possibility. Another is that sterilization prevents importation into the abdomen of cancer-causing substances."

Nevertheless, some older women may be uncomfortable with the irreversibility of the method, (11) and may more readily accept the reversible sterilization that an IUD provides. "IUDs can be safely used by healthy women of any age," note Dr. Grimes and FHI senior epidemiologist Dr. David Hubacher, who recently published a systematic review of evidence of the non-contraceptive health benefits of IUD use. (12) "Inserted when a woman is 40 years old, it can remain in place through menopause and thus may be the last contraceptive a woman needs." Furthermore, case-control studies offer fair evidence that copper-bearing and nonmedicated IUDs provide the noncontraceptive health benefit of protecting against endometrial cancer. (13)

When the Copper-T 380A IUD was introduced as an alternative to female sterilization in Rajasthan, India, researchers observed that the IUD was preferred by older women and women who had achieved their desired family size, especially tribal women. Only 30 of 216 IUDs inserted over three years were removed. IUD use gave women the freedom to change their minds about further childbearing, while reducing their dependence on doctors and on the expensive equipment needed for female sterilization. (14)

Before fitting an older woman with an IUD, providers should take into account her pre-existing menstrual pattern. If she already has dysfunctional uterine bleeding, heavy bleeding, or painful menstruation, any increased menstrual blood loss or pain associated with an IUD may be unacceptable. (15) Because an older woman is more likely to have a tight cervical canal than a younger woman, IUD insertion may be more difficult. "If a difficult insertion is anticipated," advises Dr. Grimes, "the woman can be given 400 [micro]g of misoprostol, a widely available and inexpensive drug, by mouth or vagina the night before or four hours in advance of the procedure. This will dilate the cervix. A paracervical block also can make the insertion more comfortable." An IUD should be removed after menopause since it may complicate the evaluation of any postmenopausal bleeding that may occur. Menopause will be obvious because the copper IUD does not mask the end of menses.

In contrast to copper-bearing or non-medicated IUDs, the levonorgestrel-intrauterine system (LNg-IUS) that continuously releases progestin into the uterus controls the dysfunctional menstrual bleeding that older women commonly experience. It also reduces menstrual bleeding and thus may be a good alternative to hysterectomy, which is often considered when menstrual blood loss is unacceptably heavy. Two randomized, controlled trials of the LNg-IUS as an alternative to hysterectomy showed that women offered this method were far more likely to cancel their planned hysterectomy than women assigned to continue their current, conservative medical treatments. Eighty percent and 64 percent of women in the LNg-IUS arms of the two trials canceled their surgery compared with 9 percent and 14 percent of women assigned to conservative medical treatments in the two trials. (16)

The LNg-IUS can protect the uterine lining, or endometrium, of older women receiving estrogen replacement therapy to control menopausal symptoms. (17) And its sustained release of levonorgestrel directly into the uterus may result in fewer systemic side effects than the release of progestins via pills or implants. (18)

COMBINED HORMONAL METHODS

When used consistently and correctly, the low-dose combined oral contraceptives (COCs) available today are highly effective. So, too, are combined injectable contraceptives (CICs). Regardless of their age, women who use these contraceptive methods face very little danger of adverse cardiovascular events--including thromboembolism (blockage of a blood vessel), stroke, and heart attack--as long as they have no history of cardiovascular disease and have no risk factors for cardiovascular disease, such as hypertension, diabetes, or a habit of smoking cigarettes. (COCs are contraindicated for women 35 or older who smoke 15 cigarettes or more daily, and are not recommended for women 35 years or older who smoke even fewer cigarettes. CICs are not recommended for women 35 years or older who smoke 15 cigarettes or more daily.) (19)

As a woman ages, her risk of thromboembolism and hemorrhagic stroke attributable to COC use rises. However, the incidence and mortality rates of all cardiovascular events (stroke, heart attack, and venous thromboembolic disease) in women of reproductive age are very low. The annual risk of death from cardiovascular disease attributable to COCs among users who do not have risk factors for such disease is about two deaths per million users at 20 to 24 years of age, two to five deaths per million users at 30 to 34 years of age, and approximately 20 to 25 deaths per million users at 40 to 44 years of age. (20)

COCs provide important noncontraceptive benefits. Their use by women of any age nearly halves the risk of ovarian and endometrial cancer, with protection continuing for 10 to 15 years after discontinuation and longer duration of use offering greater protection. (21) (Whether CICs offer similar protection remains unknown.) Whether COC use increases the risk of breast cancer has been the subject of two recent studies. The first, a meta-analysis, showed a small increase in risk with recent use but a significantly lower risk of metastatic disease. (22) The second, a population-based, case-control study among more than 9,000 women 35 to 64 years of age, showed that current or former COC use was not associated with increased risk of breast cancer, even among women who have close relatives with the disease. (23) Conducted by scientists at the U.S. Centers for Disease Control and Prevention and the National Institutes of Health, this is the largest study ever to examine the possible risks of breast cancer among COC users.

Meanwhile, numerous studies indicate that perimenopausal women who use COCs can preserve bone mineral density (in contrast to nonusers, who experience bone loss). This suggests that perimenopausal women who use COCs may enter menopause with stronger bones. (24)

"Another advantage of COC use is that it makes menstrual bleeding regular, like clockwork, and thus may reduce the need for invasive procedures or gynecologic surgery to diagnose or treat the irregular menstrual bleeding so common among older women," says Dr. Grimes. "While often benign, irregular bleeding in older women must be investigated to rule out the possibility of endometrial cancer."

Finally, COCs are highly effective in controlling hot flushes and other bothersome menopausal symptoms as women approach menopause. Hormone replacement therapy (HRT) can also do so at lower doses of hormones than those contained in COCs. But HRT cannot be used as a contraceptive, and growing evidence indicates that HRT's risks must be carefully balanced against its benefits. Providers should discuss those risks and benefits with women taking HRT or those planning to do so.

Five-year data from a recent large U.S. study of the major health benefits and risks of HRT use by healthy postmenopausal women showed that use of combined estrogen/progestin HRT raised the risk of stroke by 41 percent and the risk of heart attack by 29 percent, compared with placebo. (25) Other studies had indicated a short-term, increased risk of adverse cardiovascular events among postmenopausal women with established heart disease receiving combined HRT, although that risk declined over time. (26)

The large U.S. study--the Women's Health Initiative--also found that combined HRT reduced the risk of colorectal cancer and hip fractures, but raised the risk of breast cancer by 26 percent. (This increased risk led to the premature termination of the part of the study comparing estrogen/progestin HRT with placebo.) Other studies have also indicated that current or recent use of HRT for five years or longer is associated with an increased risk of breast cancer. (27) However, several epidemiological studies indicate that HRT users have a significantly lower risk of metastatic breast cancer than nonusers, (28) and use of HRT by postmenopausal women is associated with a reduced risk of death from breast cancer, according to a recent review by FHI researchers of published observational evidence on the subject. (29)

A disadvantage of COC or CIC use late in a woman's reproductive life is that prolonged use masks the onset of menopause. (A woman will continue to bleed each month as long as she uses these estrogen-containing methods.) In settings where expensive laboratory testing of fertility is not feasible or available, there are a couple of ways to ensure that menopause has occurred and that COC use can be permanently abandoned without risking an unplanned pregnancy. First, a woman can stop COC use and use a barrier method for six months. If she does not menstruate for six months, contraception can be stopped. If regular menstruation returns, she can restart the COC. After another year, she can repeat the procedure: stop COC use and use a barrier method for six months. (30) Or, a healthy nonsmoker can continue COCs until age 53 or older, when permanent cessation of ovulation is nearly certain.

PROGESTIN-ONLY METHODS

Perimenopausal women for whom estrogen is contraindicated, such as smokers and women with cardiovascular risk factors, who still wish to use a hormonal contraceptive method can safely use progestin-only injectables, pills, or implants.

However, unpredictable bleeding patterns associated with such methods--ranging from normal cycles to erratic short or long cycles, nuisance spotting, and amenorrhea--may prove unacceptable for some women. In a two-year, prospective study among 60 women older than 35 years in Bangkok, Thailand, irregular bleeding due to the use of the progestin-only, three-month injectable depot-medroxyprogesterone acetate (DMPA) was the main reason why four of every five women discontinued the method. (31) Because older women tend to have gynecological problems that cause menstrual bleeding irregularities, care must be taken to evaluate those irregularities before progestin-only methods are begun. Also, if frequent or prolonged bleeding develops during use, a gynecological cause must be ruled out. Because the return to regular menstrual cycles is long and unpredictable after DMPA use is discontinued, quick identification of menopause may be difficult.

DMPA offers the noncontraceptive health benefit of protecting against uterine fibroids (32) and may protect against endometrial cancer. (33) Its use has been associated with reduced bone density in premenopausal women, but bone density increases after the drug is discontinued. Residual effects of DMPA use on postmenopausal bone density are small and unlikely to have a substantial impact on fracture risk. (34)

For older women, levonorgestrel implants may be a better contraceptive option than progestin-only injections because they continuously release hormones in lower doses and for longer periods of time. (The six-rod Norplant implant provides safe and effective contraceptive protection for seven years; (35) the two-rod Jadelle implant, for five years. (36)) Use of the six-rod Norplant implant among 100 women ages 35 to 47 years was found to be safe and effective in a recent, one-year prospective study in Thailand. (37) "Studies of levonorgestrel implants in various countries indicate that effects on bone density, if any, are small," says Irving Sivin, a senior scientist at the New York-based Population Council who has extensively studied and helped to develop progestin-only contraceptives. "In terms of fibroids and reproductive system cancers, these implants appear neither to benefit nor harm users."

Progestin-only pills (POPs) are somewhat less effective than COCs. However, older women's reduced fertility coupled with their better adherence to the regimen of taking a POP at the same time each day offsets this lower efficacy. Two doses of POPs (providing at least 0.75 mg levonorgestrel per dose) can also be used by older women as emergency contraception to prevent pregnancy after unprotected intercourse, method failure, or incorrect method use.

WHEN CAN CONTRACEPTION STOP?

"A woman may still have some menstrual bleeding in her late reproductive years, but many of her menstrual cycles will be anovulatory," says Dr. Grimes. "And, by the time she is in her 50s, her fertility is nearly zero." Indeed, some experts suggest that women be advised to abandon contraception at the age of 50, while others recommend waiting six to 12 months after a woman's last menstrual cycle. Women who use hormonal methods that mask the cessation of menses should be advised to continue using the methods until age 53, Dr. Grimes adds.

But, regardless of an individual's age, one reproductive health consideration does not change: Consistent and correct condom use remains essential for sexually active women at risk of contracting an STI, including HIV.

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