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How does Hormonal Birth Control work?

All hormonal birth control (the pill, Nuvaring, patches, implants, injections or the Mirena) contain synthetic or “pseudo” hormones, such as ethinylestradiol, drospirenone and levonorgestrel – a.k.a estrogen and progestin.

Their role is to inhibit the production of the body’s natural hormones – oestradiol and progesterone – in order to prevent pregnancy.

This is achieved by:

  • supressing ovulation to ensure no egg is released from the ovaries
  • thickening cervical mucus to prevent sperm from entering the uterus
  • thinning the lining of the uterus to prevent implantation for a fertilized egg

Risks and side effects of hormonal birth control

Whilst hormonal birth control can be very effective in preventing unplanned pregnancies, there are a number of risk factors and side effects that should be considered:

  • Cancer – the risk of breast cancer is higher among women who have currently or recently used contemporary hormonal contraceptives, including low-dose pills, implants and the hormonal IUD.1,2
  • Blood Clots – All hormonal birth control carries a risk of blood clots
  • Depression – Girls and women who use hormonal birth control are significantly more likely to be diagnosed with depression. It makes the nervous system more sensitive to stress and alters the structure of the brain.3,4
  • Loss of libido and sex drive – this can be caused due to a reduction in testosterone.
  • Hair loss – progestins with high androgen indexes (aka high testosterone) can have devastating effects on normal hair growth, particularly for women who have a history of hair loss in the family.5
  • Weight gain – due to its interference with insulin, promotion of sugar cravings and prevention of muscle gain expected from exercise.1
  • Nutrient deficiencies – Including folic acid, vitamin B2, B6, B12, vitamin C and E, magnesium, selenium and zinc.6
  • Headaches and migraines – migraine sufferers are advised to avoid the combined oestrogen pill due to a higher stroke risk than other women. Progestin only methods may provide relief, but they can also worsen migraines in some situations.

In what situations is it ok to be on the pill?

I believe that there are only 2 situations in which someone should consider being on the pill:

  1. You understand the physiological reality of the pill, you are aware of your other options and you decide that it is the best one for you.
  2. You have a serious condition such as endometriosis or adenomyosis and as a result suffer from debilitating symptoms.

If you would like to find out more about alternatives to hormonal birth control or how you can get your menstrual cycle back on track, please click here to book in for a free 20 minute Base Chat with one of our Naturopaths.


1Briden, L. (2018). Period Repair Manual. Sydney: Macmillan Australia.

2Mørch, L., Skovlund, C., Hannaford, P., Iversen, L., Fielding, S., & Lidegaard, Ø. (2017). Contemporary Hormonal Contraception and the Risk of Breast Cancer. New England Journal of Medicine, 377(23), 2228-2239. doi: 10.1056/nejmoa1700732

3Skovlund, C., Mørch, L., Kessing, L., & Lidegaard, Ø. (2016). Association of Hormonal Contraception with Depression. JAMA Psychiatry, 73(11), 1154. doi: 10.1001/jamapsychiatry.2016.2387

4Petersen, N., Touroutoglou, A., Andreano, J., & Cahill, L. (2015). Oral contraceptive pill use is associated with localized decreases in cortical thickness. Human Brain Mapping, 36(7), 2644-2654. doi: 10.1002/hbm.22797

5American Hair Loss Association. (2010). Oral Contraceptive. Retrieved 21 November 2018, from

6Palmery, M., Saraceno, A., Vaiarelli, A., & Carlomagno, G. (2013). Oral contraceptives and changes in nutritional requirements. European Review for Medical and Pharmacological Sciences, 17, 1804-1813.