Four Decades of the Birth Control Pill
Surveys have found that as recently as 1985, three-quarters of women believed there were "substantial health risks" associated with pill use. In 1993, 54% of women distrusted the pill; in April 2000, 41% of women said they feared it. Women still cite cancer as their number one fear, when, in fact, studies have shown the pill has protective effects against certain types of cancer, says the American College of Obstetricians and Gynecologists.
Since 1970, ovarian cancer incidence and deaths have declined among U.S. women between the ages of 35 and 59. A few studies have shown that the duration of contraceptive pill use is a key factor in reducing the risk of ovarian cancer.
Stanford University researchers are among many working to further pinpoint the pill's protective effects. "The study shows that while the pill seems to protect pre-menopausal women, the protective effect may not carry over into older women," researcher Susanne Gnagy, whose study appears in the May issue of the journal Epidemiology, tells WebMD. Gnagy is an epidemiologic researcher in the Stanford School of Medicine's Health Research and Policy Department.
Another study, in the March Epidemiology, showed that oral contraceptives' protective effects against ovarian cancer multiply over time, and that they may last 15 years or more after a woman stops using the pill. There was a 7% decrease in risk for this cancer for each year of pill use, says researcher Victor Siskind, of the Queensland Institute of Medical Research in Australia.
"There was little evidence of waning protection with time ... or from early commencement of pill use," Siskind writes. "Oral contraceptives may act by both suppressing ovulation and altering the tumor-promoting [environment]."
Now that pill usage has reached maturity, we can expect more studies of the pill's effects, both long-term and short. "There haven't been many studies of women who have used the pill for a long period of time. Now that we've had 40 years of women using the pill, we're just beginning to raise questions," Gnagy tells WebMD.
While some risks of taking the pill, such as strokes and blood clots, are the same today as they were in the early 1960, "data show that the chances of someone (not on the pill) dying of a clot is 1 in 100,000; it's two or three times higher for a woman on the pill; but for a pregnant woman, the chances are 9 in 100,000," says James Roberts, MD, head of gynecology at Stanford University School of Medicine. "So you've eliminated or at least vastly decreased that problem by taking the pill (to prevent pregnancy)."