Currently over 100 million women worldwide use some form of hormonal contraceptive whether for symptom management or pregnancy prevention [1]. Access to hormonal contraceptives is a right women have fought hard for and has proven to be a relatively safe means of pregnancy prevention. However, through the years it has become significantly more common for hormonal contraceptives to be prescribed as a band-aid fix for management of unwanted symptoms rather than just pregnancy prevention. Oftentimes, women are told birth control will have no significant impact on their health but the truth behind the impacts of exogenous hormones on a female’s body are not being fully revealed. Many women are blindsided to the significant toll hormonal contraceptives have on their mental health, gut health, mineral and nutrient status, thyroid health and long-term fertility.
Before we dive into the impacts on your body, let’s summarize how birth control works to prevent pregnancy. Most hormonal contraceptives whether in the form of a pill, IUD or injection are designed to mimic progesterone and estrogen levels in the luteal phase of a woman’s menstrual cycle. We say “mimic” because they are not the actual hormones but rather synthetic versions derived from testosterone metabolites [2]. This means hormones from birth control appear chemically similar to the real progesterone and estrogen therefore it has the ability to trick your brain and body into thinking they are the real deal enabling them to bind to receptors throughout the body and alter functioning. As a review, the luteal phase occurs in the second half of a woman’s menstrual cycle after ovulation but prior to menstruation. During this time, the body begins preparing for a potential pregnancy in the event an egg was fertilized during ovulation. In preparation, progesterone levels rise significantly to promote a calming effect on the body while establishing a uterine lining for the egg to implant and soon grow [2,3]. Simultaneously, estrogen levels rise slightly but should remain relatively low in relation to progesterone. After some time, the body realizes no pregnancy has been established which causes a shift in hormones (drop in progesterone and estrogen) and the rise of hormones luteinizing hormone (LH) and follicle stimulating hormone (FSH) to begin preparing another egg for a potential fertilization [2.3]. The levels of hormones in birth control are relative to the amounts of progesterone and estrogen during this time period to trick the brain not to begin preparing another egg because there is never a decline in estrogen and progesterone. Therefore LH and FSH are never released and ovulation never occurs. Meanwhile, your body’s natural ability to create estrogen and progesterone are significantly suppressed. There are over 40 combinations of birth controls in some combination of progestin and ethinyl estradiol or progestin only, these small differences slightly vary the mechanism of this process but the outcome and impacts on the body are the same either way [1].
Estrogen and progesterone receptors are not only located throughout the reproductive system, they are located everywhere in the body: the brain, the gut, the cells, the liver, the pancreas, the adrenal gland and the thyroid gland. Interference with normal fluctuations in the rise and fall of hormones throughout a woman’s menstrual cycle by providing the same, constant hormone levels has, unfortunately, more short and long-term effects on your body than your provider has led you to believe.
References
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