Women have naturally been spooked by recent press reports that contraceptives such as the pill and coil raise the risk of breast cancer by 25 percent—but here’s why they shouldn’t panic.
The increased risk seems alarming, and it makes for arresting headlines—but that’s not the true risk.
Researchers from Oxford University have applied the measure of relative risk, which drug companies routinely do to make their drugs seem more effective.
But the measure that matters is absolute risk. A woman in her late 20s has an absolute risk of developing breast cancer of just 0.5 percent—and taking the pill increases that risk to 0.57 percent. By the time she reaches her late 30s, her risk of cancer is at around 2 percent—still very small—and the pill and coil raise that to 2.2 percent.
Putting the risk of the pill in context, one drink of alcohol every day raises the risk of breast cancer by 10 percent, and so two alcoholic drinks a day has a similar risk profile as the pill.
The researchers had monitored the health of around 30,000 women, some of whom were taking a progestogen-only contraceptive. The incidence of breast cancers in women using contraceptives for 15 years increases from 0.084 percent to 0.092 percent overall.