Understanding Estrogen, Progesterone & Reproductive Health

I remember the "talk" in high school when they separated the girls from the boys and explained to us that getting pregnant is a big no-no. Then, they explained how to avoid pregnancy, namely, the pills. I regret to say they didn't touch on the things that confused me then. Moreover, none of my OBGYNs provided any information about how the body should function and what the alarm sounds are. Understanding reproductive hormones is important for any person with ovaries, before and after menopause, as the absence of estrogen and progesterone impacts your overall health. What are hormones? Hormones are chemical messengers, like snail mail. They convey information to cells that influence mood, behavior, emotion, brain functions (like focus and memory), the immune system and reproductive and metabolic functions. All cells in the body are bathed in a broth of hormones that constantly change to adapt to factors such as light and darkness, appetite and satiation, stress levels, blood sugar and your cycle. For reproductive hormones to effectively convey their message, they need to enter the cell, and cells need to be receptive to the message. If cells are not receptive, they might turn the hormones out. Three primary hormones that manage women's reproductive system: Estrogen is the dominant hormone produced in your ovaries from the first day of menses until the middle of your cycle (about day 14). LH (Luteinizing Hormone) is produced in the pituitary gland in response to a peak in estrogen. It surges about 24 to 48 hours before ovulation. Progesterone is secreted by the corpus luteum, the transformed follicle after ovulation that becomes a temporary endocrine gland. These hormones create the three phases of the female reproductive cycle: The follicular phase is when an egg matures, and estrogen is the dominant hormone. The ovulatory phase is initiated by LH. The egg is released from the follicle and is transported through the fallopian tube. The luteal phase follows ovulation. The egg, now in the uterus, is awaiting fertilization, basking in the nutrients that estrogen built in the follicular phase. Progesterone's role is to maintain that haven for the egg until fertilization (about 14 days). Most women are aware of these hormones and how they affect reproductive health. However, what many women don't know is that reproductive hormones have a far-reaching effect on every system in the body. This means if your reproductive hormones are out of whack, so is your entire body; but also if your body is not well, you will have imbalances in the reproductive system, including premenstrual syndrome (PMS), infertility, polycystic ovarian syndrome (PCOS) and fibroids. What does estrogen do in your body? Estrogen is a building hormone. It promotes cell proliferation and blood vessel production to supply the egg and potential embryo with nutrient- and oxygen-rich blood. However, estrogen has many other functions not directly connected to reproduction. In the hypothalamus, estrogen has a cooling effect on the body's thermostat. Body temperature in the follicular phase tends to be one-half to one degree cooler than in the luteal phase, partly due to estrogen's cooling effect and progesterone's warming effect. In perimenopause, fluctuations in hormones leads to fluctuations in body temperature. Estrogen has a profound effect on the two branches of the immune system. In the innate immune system, it promotes the release of anti-inflammatory immune messengers such as IL-1β, IL-6 and TNF-α. In the adaptive immune system, it promotes Th2 (allergy and antibody production) response, suppressing Th1 (bacterial and viral infections) and Th17 (inflammation). This is why women with insufficient estrogen or post menopause see increases in inflammatory markers. Estrogen supports the cardiovascular system through multiple channels: Promotes vasodilation through increased nitric oxide production Maintains arterial integrity and elasticity, preventing age-related stiffening Reduces vascular inflammation at the cellular level Supports a healthy fat metabolism (cholesterol, triglycerides, HDL, LDL) Women with insufficient estrogen or after menopause lose the protective effect of estrogen on the cardiovascular system, which, if combined with a reduction in anti-inflammatory protection, dramatically increases the risk of developing a heart condition. In the brain, estrogen has a profound effect due to its anti-inflammatory action, and its promotion of neurotransmitters like serotonin, dopamine and GABA that keep us calm and happy, as well as acetylcholine, a vital neurotransmitter in memory consolidation. Without the protective effect of estrogen on the brain, risks of mood disorders, brain fog, memory loss and degenerative diseases are increased. By supporting GABA and serotonin sensitivity and function, estrogen promotes a good night's sleep. It also influences melatonin and the circadian cycle, enhancing REM sleep and maintaining healthy sleep stage cycling. Estrogen also supports bone strength and resilience by reducing cell breakdown in bones, supporting the protein scaffolding of bones and extending the lifespan of osteoclasts (bone-building cells). Additionally, estrogen supports synovial fluid production, helping to decrease friction in joints, absorb shocks and increase joint mobility. Estrogen is doing so much more than we may have thought it was doing in the body, and it explains why any fluctuation in estrogen affects more than just the reproductive system, evidenced by times during your cycle when you may have felt moody, had a hard time sleeping or struggled with memory or focus. You may suspect insufficient estrogen if you experience: Irregular or absent periods Very light menstrual flow Shortened menstrual cycles Infertility issues Vaginal dryness Hot flashes Joint pain Bone density loss Sleep disruption Brain fog and memory issues Mood changes, depression or anxiety Decreased libido What does progesterone do in your body? Like estrogen, progesterone is a reproductive hormone that has many effects that aren't necessarily reproductive. Progesterone balances estrogen. Estrogen is a building hormone that lines your uterus to support conception while progesterone promotes the shedding of the lining. Women with insufficient progesterone will see fibroids and heavy periods. Opposite to estrogen, progesterone increases the body's resting temperature, which is why perimenopausal women experience hot flashes. Progesterone fluctuates so dramatically that their body temperature shifts fast. Progesterone also increases the production of Treg (T-regulatory) cells which are anti-inflammatory. As long as your body releases sufficient progesterone for the 10 to 16 days following ovulation, your risk of inflammation is reduced. Progesterone acts as a calcium channel blocker, helping relax blood vessel walls and reducing blood pressure. Women post menopause lose the protective function of progesterone and are at higher risk of cardiovascular conditions. Progesterone also influences lipid metabolism and can help maintain healthier cholesterol profiles. In the brain, progesterone converts to allopregnanolone, a calming neurosteroid that acts like GABA. For those who experience a dramatic drop in progesterone, this means anxiety and irritability. Progesterone's GABAergic effects promote deeper sleep. Poor sleep quality is a cardiovascular risk factor through its effects on inflammation and metabolic function. Progesterone also stimulates osteoblast activity — bone-building cells that produce new bone matrix. Women who have irregular ovulation or anovulatory cycles, even if still menstruating, may be losing progesterone's bone-building benefits. You may suspect insufficient progesterone if you experience: "Spotting" between periods Heavy periods PMS symptoms Sleep disturbances Increased inflammation No rise in temperature in the luteal phase It's important to note that reproductive hormones don't function in a vacuum. They are influenced by stress, specifically chronic high cortisol, metabolic conditions, insulin resistance and thyroid hormones. Changes in one family of hormones lead to a chain reaction in the entire endocrine system; therefore, any reproductive system care plan will include diet, detox, metabolic health, sleep and stress management. I invite you to share this information with friends and family, especially daughters. No woman should be in the dark when it comes to understanding how reproductive hormones can change her life and how to notice when something is amiss. Maybe respecting our bodies means slowing down and being graceful with ourselves because the hormonal ups and downs women experience are not just a myth; they affect almost every facet of our lives.