MAKE AN INFORMED DECISION

Hormonal birth control is used by many women to avoid pregnancy and/or manage symptoms that range from annoying to severely painful.

but how does it work?

Before we can fully understand how hormonal birth control works to prevent pregnancy and reduce unwanted symptoms, it’ll be helpful to understand the design and function of our naturally occurring hormones.

Early in each cycle, the brain sends specific signals to trigger a sequence of important events:

 

  1. It begins with a signal (FSH) to one ovary to recruit an egg or two for development within a follicle towards ovulation. 
  2. That follicle produces estrogen, which influences the lining of the uterus to begin to thicken and become enriched and develops the cells of the cervix to produce a characteristic type of mucus (which can provide the woman with information about her body). 
  3. Another signal (LH) triggers the release of the egg. 
  4. After ovulation, a corpus luteum is formed and produces progesterone at a high level, which ultimately gives its seal of approval for implantation (of a newly conceived embryo) to an even more nutritious uterine lining. 
  5. These hormones also deliver important benefits to brain, bone, & immune function, and more, whether or not a child is conceived.

It’s the only medicine given to a healthy woman to make her body stop working the way it was designed to.

Hormonal birth control works by introducing synthetic hormones into the woman’s body in an effort to shut down this complex communication system between the brain and ovaries. This overrides her naturally occurring hormones of estrogen and progesterone to suppress ovulation. Click here to see the health benefits of ovulation.

  • When birth control was first created, it contained extremely high amounts of synthetic hormones. This was found to be very unhealthy and sometimes deadly for many women, so the amount of synthetic hormones was significantly decreased. This has decreased the harmful side effects, but it has also allowed for breakthrough ovulations to occur.

  • For the standard oral contraceptive, breakthrough ovulation occurs somewhere between 1.7% to 28.6% per cycle*.

  • For the progestin-only contraceptives, breakthrough ovulation can range between 33% to 65%*.

*REFERENCE: Larimore, W.L. and Stanford, J.B.: Post-Fertilization Effects of Oral Contraceptives and their Relationship to Informed Consent. Arch Fam Med 9:126-133, 2000.

Because of the frequency of breakthrough ovulations, hormonal contraception has two built in backup plans to prevent a full term pregnancy by:

  1. Changing the qualities of cervical mucus to make it difficult for sperm to penetrate the cervix (and impossible to gather information from) 
  2. Thinning out what would have been a thick and nutritious lining of the uterus to make it very difficult for an embryo to implant

Therefore – if breakthrough ovulation occurs and a woman engages in intercourse and becomes pregnant, this lining would likely be too thin to support the life of the newly-conceived baby. This termination would occur without the woman knowing she was pregnant.

According to Spinnato*, the main mechanism of action of the IUD is prevention of implantation of a new embryo.

*REFERENCE: Spinato, J.A.: Mechanism of Action of IUD and its Relation to Informed Consent. Am J Obstet Gynecol 176: 503-506, 1997.

If a woman uses hormonal birth control for the purpose of improving symptoms, but is concerned about this back up mechanism, it is possible for her to learn how to understand her body’s response to birth control if she is working closely with an instructor. If a breakthrough ovulation would occur, there would likely be evidence of it in her charting, and she could choose to abstain from intercourse during the fertile window.

Pill bleeds aren’t periods.

Many women use hormonal birth control with the understanding that it regulates cycles, meaning that it allows her to have consistent bleeding episodes. This may, in fact, give the woman a sense that her periods have become regular, but the bleeding she experiences is not a period bleed.

A period bleed is caused by the healthy shedding of the lining cells of the uterus so that it can be replaced by a fresh, thick, and nutritious new lining every cycle. But one of birth control’s backup mechanisms to prevent full term pregnancy is to eliminate the thick lining that would shed and be replaced.

The “regular” bleed a woman experiences when using hormonal birth control is nothing more than a “withdrawal bleed” from the removal of synthetic hormones, a purely chemical response.

Hormonal birth control & unwanted symptoms:

Many women appreciate the use of hormonal birth control as a relatively simple and mindless means of avoiding pregnancy and/or to reduce an array of symptoms. It is effective at avoiding ovulation or full term pregnancy. Although it does not have the ability to assess or treat the underlying problem causing symptoms, it does tend to reduce or eliminate those unwanted symptoms while the woman is using it. 

We recommend consulting a restorative reproductive medical professional from our “external resources” tab.

There is no research to support the idea that hormonal suppression ceases the growth of endometriosis lesions. See: Endometriosis in Adolescents: A Systematic Review – Patrick Yeung, Shweta Gupta, Sam Gieg, 2017 (sagepub.com). It does not cure PCOS.

Be aware that symptoms of any underlying condition often return once birth control is stopped. It is common for the woman to experience unwanted side effects when using the pill, patch, or IUD (hormonal birth control), including:

  • Headaches
  • Nausea
  • Decreased libido
  • Breast tenderness
  • Cramping
  • Mood changes
  • Weight changes
  • Vaginal discharge

Regardless of which method you choose and for whatever reason, be fully informed. There are difficult aspects of every option from birth control to fertility awareness, so it is simply a matter of what the woman is willing to give up. A truly empowered decision cannot be made without having all the information.

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