The pill does not give you cancer. In some very rare cases, women may get a blood clot. The risk of getting a blood clot while taking the pill is lower than the risk of getting a clot while pregnant. Some women have medical problems that mean they should not use the pill.
If you are healthy, contraceptive pills are very safe. They can help you with some problems now (like anemia from heavy periods) as well as later in life (they may protect you against some kinds of cancer)[1].

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References:

1. World Health Organization Department of Reproductive Health and Research and Johns Hopkins Bloomberg School of Public Health Center for Communication Programs (2018) Family Planning: A Global Handbook for Providers. Baltimore and Geneva. Retrieved from https://apps.who.int/iris/bitstream/handle/10665/260156/9780999203705-eng.pdf?sequence=1