A woman's risk of developing breast cancer depends on several factors. While some are related to her natural hormones, others are linked to reproductive history factors. Beginning menstruation at an early age, not having children, or experiencing menopause at a late age are factors that may increase the risk of breast cancer.
Several studies have shown that women who use or have ever used the pill have a slightly higher risk of developing breast cancer than those who have never used it. The risk is a bit higher if the woman started using it as a teenager.