Birth Control Pills & Breast Cancer
Breast cancer is every woman’s nightmare. Breasts are a sign of femininity. When this is threatened, females get understandably nervous to their core.
Do oral contraceptives, which typically contain synthetic estrogens and progestins, increase the risk of breast cancer?
Research Studies
Jordanian researchers, looking at 450 Jordanian women (225 as cases and 225 as controls), aged 18 to 65, said yes.
Results: Results indicated that regular use of OCs exhibited an association with increased risk of breast cancer, while the duration of OCs use was not associated with the increased risk of breast cancer. In addition, other factors demonstrated significant association with the increased risk of breast cancer such as age at puberty, age at menopause, previous pregnancies, menopausal status, and family history of cancer.
Conclusions: Regular use of OCs may be associated with an increased risk of breast cancer in Jordanian women.
Polish researchers found different results.
Polish statistics and virology scientists conducted a systematic review of the literature with meta-analysis in order to quantitatively estimate this association between the use of oral contraceptives and the future risk of breast cancer.
They searched bibliographic databases MEDLINE and EMBASE, and reference lists of identified articles, with no language restrictions, from the start of publication of that journal to August 2010. They performed a reanalysis and overall estimate of 79 case-control studies conducted between 1960-2010, including a total of 72,030 incidents, histologically confirmed cases of breast cancer, and 123,650 population/hospital controls. There was no significant increase in risk among premenopausal women (1.06, 0.92-1.22), postmenopausal women (0.99, 0.89-1.10), or nulliparous women (1.02, 0.82-1.26).
Oral contraceptives do not appear to increase the risk of breast cancer among users.
However, OC use before a first full-term pregnancy or using them longer than 5 years can increase the development of breast cancer.
The Italian National Cancer Institute
The Italian National Cancer Institute discusses the publication of two studies that analyzed data from women receiving low-dose hormonal contraception and showed a statistically significant increase in breast cancer contradicting the old belief that birth control is safer on breasts.
We know birth control pills reduce the risk of ovarian cancer. That is well studied. All authors do remind us that patients must be informed that notwithstanding the slightly increased breast cancer risk.
If you take birth control, what boosts breast cancer risks, you need to know this, too.
Being overweight, smoking, or having a family history. So if you are chubby, smoke or have first-degree relatives with breast cancer, realize this.
Knowledge is power.
Also, remember that oral birth control pills are definitively linked to an increased risk of inflammatory bowel disease in those with a genetic risk or altered biome.
Research from Budapest
Budapest researchers also took a look as most countries want to know the risk versus safety features of birth control pills.
They write: At present, an estimated hundred million women worldwide use oral contraception, but the influence of hormonal contraception on the carcinogenesis of breasts is not fully understood. Previous studies of breast cancer risk show inconsistent findings - from zero elevation to approximately 30%-40% increase in risk.
The beneficial effect on ovarian and endometrial cancer risk is apparent. In this literature review, they attempt to determine the effects of oral contraception in relation to the risk of breast cancer.
The risk increased with a longer duration of use, but the absolute increase is very small. "Beneficial effects of OCs on the gynecological cancers thus outweighed adverse effects."
Then, why are older women denied hormones if the most altered and potentially risky forms, oral and synthetic progestins, are now available OTC and are reported to be okay even with small confirmed higher risks of getting breast cancer?
The Durham VA Hospital Group
The Durham VA hospital group looked at birth control use and the risk of breast cancer. As well as other cancers. They said in their abstract:
Oral contraceptives may influence the risk of certain cancers.
As part of the AHRQ Evidence Report, Oral Contraceptive Use for the Primary Prevention of Ovarian Cancer, we conducted a systematic review to estimate associations between oral contraceptive use and breast, cervical, colorectal, and endometrial cancer incidence.
We searched PubMed, Embase, and Cochrane Database of Systematic Reviews. Study inclusion criteria were women taking oral contraceptives for contraception or ovarian cancer prevention; includes comparison group with no oral contraceptive use; study reports quantitative associations between oral contraceptive exposure and relevant cancers; controlled study or pooled patient-level meta-analyses; sample size for nonrandomized studies ≥100; peer-reviewed, English-language; published from January 1, 2000 forward.
We included 44 breast, 12 cervical, 11 colorectal, and 9 endometrial cancers studies.
Breast cancer incidence was slightly but significantly increased in users (OR, 1.08; CI, 1.00-1.17); results show a higher risk associated with more recent use of oral contraceptives.
The risk of cervical cancer was increased with the duration of oral contraceptive use in women with human papillomavirus infection; heterogeneity prevented meta-analysis.
Colorectal cancer (OR, 0.86; CI, 0.79-0.95) and endometrial cancer incidences (OR, 0.57; CI, 0.43-0.77) were significantly reduced by oral contraceptive use.
Compared with never use, ever use of oral contraceptives is significantly associated with decreases in colorectal and endometrial cancers and increases in breast cancers.
Although elevated breast cancer risk was small, the relatively high incidence of breast cancers means that oral contraceptives may contribute to a substantial number of cases.
Knowledge is power… if lived.
If you have first-degree relatives, if cancers run in your family, if you smoke, are overweight, or want to get pregnant in the near future, if you started menstruation early (11 years old or younger), if inflammatory bowel disease runs in your family, if stroke and hypertension run in your family, you may just say NO to oral birth control pills.
Dr. B.
References:
Oral contraceptive and breast cancer: do benefits outweigh the risks? A case - control study from Jordan. BMC Womens Health. 2019 Jun 3;19(1):72. doi: 10.1186/s12905-019-0770-x
Use of Oral Contraceptives as a Potential Risk Factor for Breast Cancer: A Systematic Review and Meta-Analysis of Case-Control Studies Up to 2010. Int J Environ Res Public Health. 2021 Apr 27;18(9):4638. doi: 10.3390/ijerph18094638
Breast cancer risk of hormonal contraception: Counselling considering new evidence. Crit Rev Oncol Hematol. 2019 May;137:123-130. doi: 10.1016/j.critrevonc.2019.03.001
[Oral contraception and the risk of breast cancer. Review of the literature]. Magy Onkol. 2018 Dec 12;62(4):258-263. Hungarian. Epub 2018 Sep 10