Why You Need Your Period

Time and time again I have worked with patients who have been told they don’t need a period, and perhaps you have been told the same thing.  This couldn’t be further from the truth!  The menstrual cycle plays an important role in a woman’s overall health and in fact, having a natural menstrual cycle significantly contributes to optimal health and disease prevention.  By natural menstrual cycle, I mean a menstrual cycle free from synthetic hormones found in hormonal birth control.  To understand the difference, let’s outline what happens during the natural menstrual cycle and what happens when you take the Pill or other forms of hormonal birth control.

The natural menstrual cycle is broken into two phases, the follicular phase, and the luteal phase.  During the follicular phase, follicles on the ovary mature and produce estrogen.  Rising estrogen during this phase helps to thicken the uterine lining and open the cervix.  Peak estrogen production produces sperm friendly, fertile mucus and one follicle becomes dominant that will release an egg at ovulation (the main event of the menstrual cycle).

The second phase of the menstrual cycle is known as the luteal phase.  During the luteal phase, the hormone progesterone is dominant.  Progesterone enriches the uterine lining with blood vessels, providing nutrients for possible implantation of a fertilized egg.  If implantation does not occur, estrogen and progesterone levels drop, and vaginal bleeding or a “period” occurs.

Menstrual bleeding is a predictor of how balanced the previous cycle’s hormones were and how healthy ovulation was.

On the Pill and other forms of hormonal birth control, your body is “tricked” into thinking it has already ovulated by providing elevated levels of synthetic estrogen and progesterone.  As a result, ovulation does not occur.  Additionally, the Pill thickens and dries up the cervical mucus by blocking the body’s effect of estrogen.  And finally, the Pill thins the uterine lining by suppressing the body’s own natural estrogen and progesterone. The only reason bleeding occurs on the Pill is due to the withdrawal of synthetic hormones during the week of sugar pills.  Ultimately, your “cycle” on the Pill is not actually a cycle at all.

There are 5 major health benefits of having a natural menstrual cycle:

1. Breast Health and Development

During puberty, estrogen produced via ovulation causes enlargement of breasts by increasing fatty tissue in the area and developing lobes, lobules, milk ducts and fibrous connective tissue that will produce and carry the milk to the nipple in the future.  Teens that take hormonal birth control are deprived of their cycle and the endogenous estrogen required for the proper breast development.

2. Brain Health and Development

Estrogen in the follicle phase of the cycle increases serotonin receptors and the production of dopamine. Serotonin and dopamine cause neuron (brain cell) excitability, which stimulates plasticity in the hippocampus, amygdala, and prefrontal cortex of the brain.  The neuron excitability leads to an upbeat mood, increased energy levels, and improved verbal skills.  Progesterone in the luteal phase of the cycle heals and maintains brain cells.  Feelings of mellowness and decreased anxiety are experienced during this phase.

Exposure to endogenous and balanced hormones achieved through regular ovulation and menstruation is especially important for developing teen brains as their prefrontal cortices are not fully matured until mid-twenties thus affecting their decision making and risk assessment. Additionally, brain development under exposure of endogenous and balanced hormones helps to retain brain plasticity for women after menopause.

Unfortunately, the synthetic estrogen and progesterone found in hormonal birth control options do not have the same effect on the brain.  In fact, the synthetic hormones decrease serotonin levels and increase sex hormone binding globulin (SHBG), which makes it harder for the body to use naturally occurring sex hormones.  As a result, those on the Pill often complain of low libido, mood disturbances, brain fog, disrupted sleep cycles, difficulty regulating body temperature, appetite, heart rate and difficulty managing stress.

3. Immune System

The cyclical nature of estrogen and progesterone during the two phases of the menstrual cycle impact the immune system.  During the follicular phase when estrogen is highest, the immune system is also heightened.  In the luteal phase when progesterone is dominant, there is a temporary immune suppression as the body prepares for a potential pregnancy.  The cyclical nature of heightened and suppressed immune function during the menstrual cycle is important for the maturation of the cervix, important for the proper production of cervical mucus.  Cervical mucus is an important part of the immune system as it is rich in immune regulating proteins to fight infection.  Therefore, a cervix that has been able to mature under the natural cycling of hormones is better able to fight off infection like human papilloma virus (HPV).

Hormonal birth control prevents the natural cycling of estrogen and progesterone by providing a continuous amount of synthetic hormones throughout the cycle, thus preventing the natural cycling of immune response.  As a result, use of hormonal contraception may compromise one’s immunity to reproductive and systemic infection.

4. Heart Health

Findings have shown that a woman’s resting heart rate fluctuates throughout the menstrual cycle.  During the follicular phase, resting heart rate is slower due to higher estrogen compared to a more rapid heart rate caused by progesterone during the luteal phase. In addition, estrogen helps to prevent the buildup of calcium in the arteries to help prevent coronary artery calcification (CAC).  This is important because CAC can lead to heart disease, the number one cause of death in post-menopausal women.  Progesterone is also important for heart health as it decreases blood pressure by dilating the blood vessels.

The synthetic forms of estrogen and progesterone found in hormonal birth control do not provide the same benefit as the naturally occurring hormones in a menstrual cycle.  And in fact, because you do not have a cycle on hormonal birth control, the cardiovascular benefits experienced during a natural menstrual cycle are lost.  As a result, hormonal birth control use is linked to increased risk of blood clots, stroke, heart attack, high blood pressure, diabetes, and high cholesterol.

5. Bone Health and Development

Estrogen promotes bone growth and prevents bone break down.  Likewise, progesterone is involved in the formation and maintenance of bone and in the prevention of osteoporosis. Natural ovulation and menstruation are required for healthy bones.  The first 25 years of a woman’s life is spent building bone mass and if ovulation is happening normally, a woman should be able to keep the bone mass throughout her reproductive years and beyond.  If ovulation during prime reproductive years does not occur, bone density will be negatively impacted, and those effects will manifest during post-menopausal years.

Unfortunately, the synthetic hormones in hormonal birth control do not have the same benefit on bone health.  In fact, the synthetic progesterone (progestin) found in hormonal birth control decreases the ability to build bone mineral density.

As you can see, the intricate cycling of estrogen and progesterone during a natural menstrual cycle is crucial for optimal health!

One of my favorite resources for information on women’s health including the menstrual cycle, birth control pill and fertility awareness methods is Natural Womanhood.  My article was a summary of the research they compiled.  For more in-depth reading on the above information, please click here.