Women who take the contraceptive Pill have a slightly higher risk of breast cancer. This risk disappears within about 10 years of stopping the Pill.
The older you are when you are taking it, the higher the risk of breast cancer from taking the Pill. For example, if 20,000 women took the Pill from when they were 16 to when they were 19 years old, one would be diagnosed with breast cancer because of it. But, if the same number of women took the Pill from when they were 25 to when they were 29 years old, nine would get breast cancer because of it.
These numbers are mostly based on women who used the Pill in the 1960s, when three years’ use was the average. The risks might be larger if you take the Pill for a longer time.
On the positive side, the Pill protects against ovarian cancer, and the breast cancers in women who have used the Pill tend to be smaller and easier to treat.
There are other benefits and risks of the Pill that you should weigh up. For example, it is very reliable for preventing pregnancy, but it can increase the risk of stroke (although this risk would still be small).
What about women with a family history of breast cancer?
There is little evidence that the risk of breast cancer with the Pill is increased more for women with a family history of breast cancer. Also, because a family history of breast cancer often goes hand in hand with a higher risk of ovarian cancer, the Pill’s protective effect against ovarian cancer would be beneficial. If your mother or sister has had breast cancer, it is important for you to talk about these
issues with your doctor.
What about low dose Pills?
There isn’t a lot of information about the risk of breast cancer with different doses of oestrogen, but the dose does not seem to make a difference.
What about the different types of oestrogen and progestogens?
The most commonly used Pills have a combination of an oestrogen and a progestogen. There are a few different types of these hormones – for example, ethinyloestradiol is a type of oestrogen and levonorgestrel and norethisterone are types of progestogen. There doesn’t seem to be any difference in breast cancer risk with these various different types of hormones.
What about progestogen-only Pills?
Progestogen-only pills do not seem to increase the risk of breast cancer. Progestogen can also be injected to prevent pregnancy, and there is no evidence to say that this increases the risk of breast cancer.