Key points
- Among the many benefits oral contraceptives (OCs) offer perimenopausal women are effective contraception, a stable menstrual cycle, protection against ovarian and endometrial cancers, an easing of vasomotor symptoms, and prevention of bone loss.
- The World Health Organization (WHO) recently found that nonsmoking, normotensive, nondiabetic women who use OCs—at any age—face no increased risk of myocardial infarction compared with nonusers.
- OCs increase the risk of venous thrombosis from a baseline risk of less than 1 per 10,000 person-years in nonusers to 3 to 4 per 10,000 person-years in oral contraceptive users.
- If a perimenopausal patient is doing well on OCs, it is generally safe for her to continue taking them until the age of 55, by which time menopause has usually occurred.
A 37-year-old patient who has been taking oral contraceptives (OCs) for several years announces during her annual exam that she wishes to discontinue them. Since she is nearing perimenopause—the 2 to 8 years leading up to the cessation of menses—she is concerned about adverse effects with long-term OC use. To prevent pregnancy, she plans to undergo tubal ligation.
With the new formulations available, women can safely take OCs until menopause occurs.
When you point out that she is stopping OCs just when they have the potential to be most beneficial, the patient appears quite surprised. You explain that, as women approach perimenopause—which can begin as early as the late 30s—they tend to become hyperestrogenic, with reduced luteal-phase progesterone levels. These changes can lead to menorrhagia, anemia, hyperplasia, or growth of fibroids. Because oral contraceptives suppress ovarian hormone production, they help treat and prevent these conditions.
Positive effects
OCs have so many beneficial effects, I often recommend them as a patient’s primary preventive strategy during the perimenopausal years. I encourage women who are doing well on OCs to stay on them, and I search for reasons to initiate them in women who are having any menstrual difficulties. As indicated in Table 1, they serve as effective contraception, help stabilize the menstrual cycle, protect against ovarian and endometrial cancers, ease vasomotor symptoms, and prevent bone loss.1-3
If a woman continues taking OCs until menopause, she need not resort to sterilization for birth control, as many perimenopausal women do. Further, since OCs do not increase the growth of fibroids, they can be used even by women with this pathology.3-5
With OCs, women’s premenstrual symptoms generally ease.1 Because they inhibit ovulation, the pills also reduce the incidence of functional ovarian cysts and ovarian cancer, as well as the rate of endometrial cancer and menstrual-related pelvic pain.6-11 Indeed, with perimenopausal OC use, the need for further diagnostic and therapeutic interventions is greatly diminished, since the pills are so effective in preventing and treating a range of gynecologic problems involving the endometrium, myometrium, and ovary, including abnormal uterine bleeding and ectopic pregnancy.
In the breast, OCs reduce the incidence of fibrocystic lesions and fibroadenomas.12 In bone, they increase bone mineral density (BMD) and lower the hip-fracture rate during menopause in women who use them after the age of 40.13-19 There also is evidence that OC users have a lower incidence of arthritis and a diminished risk of colorectal cancer.20-25
Oral contraceptives and perimenopause: frequently asked questions
<huc>Q</huc> What is perimenopause and when does it start?
<huc>A</huc> Perimenopause is the 2- to 8-year interval before menstruation ceases completely. It usually begins around the age of 45, but may start as early as a woman’s late 30s or as late as the age of 50.
In perimenopause, the length of the menstrual cycle begins to fluctuate, as does the production of estrogen by the ovaries. Hot flushes, night sweats, and other “vasomotor symptoms” often result. Many perimenopausal women go through a “hyperestrogen” phase that can lead to heavy periods and growth of fibroids.
<huc>Q</huc> My periods are already so infrequent, why should I worry about birth control?
<huc>A</huc> In some ways, perimenopausal women face a greater risk of unintended pregnancy than their younger counterparts, since menstrual cycles tend to become more erratic as menopause approaches, making it difficult to determine when ovulation occurs.
But the pill offers other benefits besides birth control. For example, it stabilizes the menstrual cycle and protects against ovarian and endometrial malignancies. It eases vasomotor symptoms and helps prevent bone loss, reducing a woman’s risk of bone fractures after menopause. There is even evidence that it helps protect against arthritis and colorectal cancer.
<huc>Q</huc> Who should NOT take birth control pills?
<huc>A</huc> Women who are pregnant or seeking to become pregnant should not take oral contraceptives (OCs). Nor are estrogen-containing OCs recommended for breastfeeding women. In addition, they should be avoided by women with a history of heart attack, thromboembolism, stroke, breast cancer, or serious liver disease. Women over 35 who smoke or have other risk factors for cardiovascular disease, e.g., hypertension and/or morbid obesity, also should avoid OCs.
<huc>Q</huc> What if I have uterine fibroids? Are oral contraceptives safe?
<huc>A</huc> Yes, the pill is considered safe even in the presence of fibroids. However, your doctor should be advised of your condition at the time OCs are prescribed.
<huc>Q</huc> Don’t OCs increase the risk of breast cancer?
<huc>A</huc> Although some recent research suggests a slightly elevated risk of breast cancer with the use of OCs, that increase may reflect the more intensive monitoring for cancer among women who are studied, or an increase in the diagnosis of local tumors (as opposed to systemic disease). Other research has found a decrease in the rate of metastatic breast disease with OC use. Further, the pill appears to reduce the incidence of fibrocystic breast masses and fibroadenomas.
<huc>Q</huc> What about side effects?
<huc>A</huc> Fortunately, the new OCs contain lower doses of estrogen, making major side effects less likely to occur. While a woman may experience any of a number of “nuisance” effects, these usually resolve on their own within 1 to 3 months of use. They include nausea, headache, breast tenderness, bloating, mood swings, and breakthrough bleeding. If these side effects persist, they often occur during the hormone-free interval and can be reduced or eliminated by increasing the active pill interval and decreasing the number of days off. Discuss this option with your health-care provider.
<huc>Q</huc> Don’t OCs cause women to gain weight?
<huc>A</huc> The newer formulations do not appear to. A recent study found no difference in weight gain between women on the pill and those taking placebo.
<huc>Q</huc> Isn’t it dangerous to take the pill for more than a couple of years?
<huc>A</huc> Not among healthy nonsmokers. In fact, some benefits such as prevention of bone loss and ovarian cancer occur with long-term use.
<huc>Q</huc> How will I know when I reach menopause if I’m taking the pill?
<huc>A</huc> With the new formulations available, women can safely take OCs until menopause occurs—usually around the ages of 52 to 55. One way to determine whether you have reached menopause is to have your levels of follicle-stimulating hormone (FSH) measured. If they exceed a certain level, menopause is likely to have occurred. Ask your doctor about this and other ways of assessing menopausal status.