Hailed as one of modern medicine’s greatest advancements, the pill is one of the most commonly prescribed drugs in the world.
But new evidence released over the weekend claims that those who have recently taken contraceptive pills have a 50 per cent higher risk of developing breast cancer. Women who were on a pill with a particularly high level of oestrogen almost tripled their risk of getting breast cancer, while a pill with just a moderate amount of the hormone increased the risk by roughly 60 per cent.
Published in the journal Cancer Research, scientists at the Fred Hutchinson Cancer Research Center and the University of Washington in Seattle followed 1,102 women who were diagnosed with breast cancer, most of whom were in their 40s. Taking a close look at their pharmaceutical records – in particular, the type of oral contraceptive they were taking – scientists divided them into three categories: those on a low dose of ethinyl estradiol (about 20 micrograms), those taking a moderate dose (30 to 35 micrograms of ethinyl estradiol or 50 micrograms of mestranol) and those on a high dose of 50 micrograms of ethinyl estradiol or 80 micrograms of mestranol.
Their overall finings showed that women who recently took oestrogen pills were 2.7 times more likely to have breast cancer, while those who took moderate-dosed pills were about 1.6 times more likely. There was no increased risk for the low-dose pills. This is because oestrogen acts as a signal to the breasts to stimulate the growth of epithelial cells, which is why it often leads to enlarged breasts when taking the pill. But, an unregulated growth, in turn, could become a cancerous tumour.
The results are consistent with previous studies that have found that breast cancer risk increases slightly with some oral contraceptive pills, though other studies have not found such a link.
Confused? It’s difficult to imagine a world where the pill isn’t an option. But, the good news is that high dose oestrogen pills are rarely prescribed by doctors. Also, previous studies have shown that the pill has cancer-fighting properties, too; it’s been shown to protect slightly against ovarian and endometrial cancer.
Finally, all medicines carry risks. “Every time I prescribe something for one of my patients, there’s always a balance between risk and benefit,” said Owen Montgomery, chairman of the department of obstetrics & gynecology at Drexel University in Pennsylvania.
“If aspirin came with a package insert, you’d be scared to death to take aspirin.” For Montgomery, all this study shows is that, “you have to make sure that with your patient, for her unique history, that you use something where the benefit outweighs the risk. For the vast majority, the usefulness of the pill outweighs the risk by a huge margin.”