Abstract
“The use of the levonorgestrel intrauterine device effectively treats heavy menstrual bleeding, even when associated with adenomyosis or leiomyomas, and is as effective as endometrial ablation in reducing heavy menstrual bleeding.”
Is contraception needed for women aged 40 years & older who do not desire to be pregnant?
In 2008, there were 274 induced abortions per 1000 live births among women 40 years of age or older; this ratio was higher than all age groups except for young women and adolescents (<24 years) [1].
Overall, the pregnancy rate in women over 40 years of age is low. In 2011, the fertility rate in the USA among women aged 40–44 and 45–49 years was 10.3 births per 1000 women and 0.7 per 1000 women, respectively. This compares with 107.2 births per 1000 women aged 25–29 years. Women over 40 years of age have lower fecundity (chance of birth per menstrual cycle) and, therefore, take longer to conceive. In one study, the fecundity of women younger than 35 years of age was 0.2 compared with 0.12 for women aged 35–40 years and 0.06 for women over the age of 40 years [2]. Nevertheless, the age-related decline in fecundity does not provide the basis for reliable contraception. Women of older reproductive age who do not wish to conceive need to use effective contraception until menopause.
Women over the age of 40 years who conceive are more likely than younger women to suffer adverse consequences. Older gravidae experience an increased risk of spontaneous abortion and chromosomal abnormalities, as well as a higher incidence of gestational diabetes, hypertension, placenta previa, cesarean delivery, perinatal mortality and maternal mortality [3]. In the USA, 48% of pregnancies among women aged 40 years and older are unintended. Each of these observations underscore the importance of effective contraception for women of older reproductive age who desire it.
What are women aged 40 years & older using for contraception?
Among US women aged 40–44 years who are using contraception, 50.2% rely on female sterilization, 19.6% on male sterilization, 11.1% on oral contraceptives (OCs), 8.8% on condoms, 4.2% on intrauterine devices (IUDs) and 1.1% on depot medroxyprogesterone acetate (DMPA). The USA has had higher sterilization rates compared with other developed countries [4]. Since long-acting reversible contraceptives, collectively known as LARC (IUDs and contraceptive implants), provide effectiveness comparable to that of sterilization and are substantially more cost effective than sterilization, use of these methods should be promoted among older women as they are among younger women.
Contraceptive use in women aged 40 years or older: is it riskier?
The added risks of pregnancy for women aged 40 years and older must be weighed against the risks of contraceptive use. Risks associated with the use of some methods may increase with age and additional comorbidities. For example, although the incidence of venous (deep venous thrombosis and pulmonary embolism) and arterial (myocardial infarction and cerebrovascular accident) events are low, these risks increase with age. This should be considered before initiating a contraceptive in a woman aged 40 years or older. However, because lean, healthy, nonsmoking women are at low risk for these rare events, they can use any method, including combined methods (estrogen–progestin pills, patch and vaginal ring), until menopause [101]. Since older reproductive age women are less fecund and more compliant in using contraception, the failure rate of combined methods is lower in this group of women.
The most effective reversible methods of contraception are LARC methods: the copper and progestin IUDs and the progestin implant. Since the copper IUD is nonhormonal, and the hormonal IUD and implant do not contain estrogen, their use is not associated with an increased risk of cardiovascular events. In large prospective trials of users of progestin-only methods (pills, injections, implants or IUDs), no substantial increase in the overall incidence of venous thromboembolism (VTE), myocardial infarction or cerebrovascular accidents has been noted [5–7]. Therefore, safe, effective options are available for the high-risk woman over 40 years of age.
“Women of older reproductive age who do not wish to conceive need to use effective contraception until menopause.”
The use of combined methods doubles the risk of VTE for women of reproductive age, from four to five per 10,000 to eight to ten per 10,000 women-years [8]. Since pregnancy increases VTE risk by six-times, the benefits of any contraceptive use outweigh the risks of unintended pregnancy. However, conditions such as obesity, diabetes, hypertension and migraines, as well as cigarette smoking, raise an individual's baseline risk for adverse cardiovascular outcomes. For women at elevated risk for cardiovascular events, the inherent risks of their condition compounded with the risk of using combined methods is typically too high. For example, among OC users, obesity (BMI >30) further increases VTE risk by approximately three times [9]. In addition, the risk of VTE increases with age; the incidence of VTE in reproductive aged women (five per 10,000 women-years) is less than half the rate of VTE in women of all ages (11 per 10,000 women-years) [8]. The American College of Obstetricians and Gynecologists advises caution when prescribing combined methods to obese women over 35 years of age. The US CDC recommends that for women over 40 years of age who have cardiovascular risk factors, combined methods should only be used when no other methods are available or acceptable [101].
What are the noncontraceptive benefits of contraception for women aged 40 years & older?
Approximately 4–6 years prior to menopause, women will enter the perimenopause and will likely experience changes in menstrual bleeding such as excessive or irregular menstruation, and vasomotor symptoms, such as hot flashes and night sweats. Hormonal contraceptives are treatment options for these conditions.
The use of the levonorgestrel IUD (LNG-IUD) effectively treats heavy menstrual bleeding, even when associated with adenomyosis or leiomyomas, and is as effective as endometrial ablation in reducing heavy menstrual bleeding [10]. The LNG-IUD leads to a 97% reduction in menstrual blood loss by 12 months. Although irregular bleeding can occur initially, amenorrhea rates of 20–80% have been reported at 12 months [11]. In addition, the LNG-IUD has been found comparable to hysterectomy in improving hematologic parameters and quality of life [12]. The LNG-IUD is licensed in the UK for protection from endometrial hyperplasia during use of estrogen therapy by perimenopausal and menopausal women [11]. This provides an excellent option for women who need contraception or suppression of abnormal uterine bleeding. Use of injectable contraception (or DMPA) also leads to high rates of amenorrhea and is an option for the treatment of heavy menstrual bleeding, although it has been studied less for this indication [13].
Use of combination contraceptives results in regular withdrawal bleeding, reduces menstrual blood loss, increases hemoglobin concentrations and is supported in clinical practice guidelines [11]. Combination contraceptives can also relieve severe vasomotor symptoms. Perimenopausal women taking OCs with 21 active pills may experience hot flashes during hormone-free days. These women may benefit from extended or continuous combination contraceptive regimens or monthly formulations that include fewer than 7 hormone-free days [10].
“With the availability of long-acting reversible contraceptives, almost all women can use safe, effective contraception options until menopause.”
A reduction in the risk of endometrial and ovarian cancer represents another benefit for women over 40 years of age using contraceptives. Compared with nonusers, use of estrogen-containing OCs is associated with a 50% lower risk of endometrial cancer [10,14]. The longer a woman uses estrogen-containing OCs, the lower her risk of endometrial cancer, although use for as little as 12 months confers moderate protection. The use of DMPA and the copper IUD are also associated with a reduction in risk of endometrial cancer [15]. Although no epidemiologic data address the risk of endometrial cancer in women who have used the LNG-IUD, a substantial literature has documented the efficacy of this device in treating endometrial hyperplasia and in preventing endometrial hyperplasia in women using menopausal estrogen therapy [11].
There is also robust evidence that use of OCs reduces risk of ovarian cancer. A collaborative meta-analysis reviewed 45 studies that compared users of OCs to never-users, finding a 27% reduced risk of ovarian cancer for users compared with never-users. The relative risk decreased by 20% for every 5 years of use, and the protective effect was still present 30 years after stopping [16]. DMPA use and tubal sterilization are also associated with a decreased ovarian cancer risk [17,18].
Can women safely use contraception until the age of menopause?
With the availability of LARC, almost all women can use safe, effective contraception options until menopause. The copper IUD can be used until menopause, defined as amenorrhea for at least 1 year in a woman 50 years of age or older. Use of less-effective barrier methods may also be acceptable, if the risks of unintended pregnancy are determined to be low based on frequency of intercourse or number of comorbidities. Progestin-only methods may be continued up to 55 years of age since amenorrhea is a common side effect and, therefore, cannot be used as a marker for diagnosing menopause. If women develop contraindications, including breast cancer or worsening cardiovascular disease, the benefits of decreased bleeding and endometrial protection may outweigh risks of continued off-label use [5–7]. Alternatively, switching to a nonhormonal method may be considered.
“There are no contraceptives that are contraindicated based on age alone.”
Lean, healthy, nonsmoking women of reproductive age are at low risk for cardiovascular events, and may use combined methods until 55 years of age. As with progestin-only methods, using amenorrhea to diagnose menopause may not be reliable. Likewise, assessing follicle-stimulating hormone levels in women using hormonal contraceptives is not a reliable strategy for diagnosing menopause [10]. Importantly, VTE risk for users of estrogen-containing OCs increases with age. Therefore, for women who acquire cardiovascular risk factors as they age, switching to a progestin-only or nonhormonal method is recommended [101].
When is surgical sterilization appropriate?
For women who desire permanent cessation of fertility, laparoscopic or hysteroscopic tubal sterilization or vasectomy for a male partner are options. For women who have relative contraindications to laparoscopy or general anesthesia, such as obesity, medical comorbidities or adhesions from previous surgery, hysteroscopic placement of tubal inserts is less invasive and can be performed under sedation. Older women are less likely to experience regret after permanent sterilization [19].
How should clinicians counsel women aged 40 years or older about contraceptive use?
Counseling on initiation or continuation of contraception for women aged 40 years and older should be individualized and include benefits of available methods, age-related risks of particular methods, age-related fertility rates and risks of pregnancy complications due to age or comorbidities. As with younger women, highlighting the safest, most effective options, LARC, is recommended. There are no contraceptives that are contraindicated based on age alone [101]. Evidence-based resources are available to assist providers in discussing benefits and risks with patients. The 2010 US Medical Eligibility for Contraceptive Use provides current evidence-based guidelines on the safety of contraceptive methods for women with various medical conditions and characteristics [101]. It is available for smart phones, online and in print.
What next?
Clinical trials that include older contraceptive users would provide additional data on the effectiveness and safety of contraceptive use in this population, enabling women over 40 years of age and their clinicians, to make more informed choices.
Financial & competing interests disclosure
C Cwiak receives research support from Medicines 360 for an intrauterine device clinical trial and is a consultant for Shook, Hardy and Bacon for intrauterine device-related litigation. R Allen is a Nexplanon trainer for Merck. AM Kaunitz consults with Bayer, Merck and Teva, companies that market contraceptives. His institution receives research funding from Agile and Teva, companies that market contraceptives. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.