A quick reminder (or as I like to put it, a 101 course on menstrual cycles):
Two ovarian hormones are responsible for your menstrual cycles; estrogen and progesterone. Each has some amazing effects on your tissues and may instigate good days and bad days. Estrogen begins to be synthesized from cholesterol within the ovary on day one of your cycle (when your period starts). It’s production in the primitive eggs your born with (called follicles) is “commanded” by the pituitary release of FSH (follicular stimulating hormone), which in turn is produced in response to the low levels of estrogen that occur just before the onset of your period. Levels of estrogen begin to exponentially rise about a week before ovulation and peak just a day before. This estrogen peak then sensitizes the pituitary and it responds with a surge of LH (luteinizing hormone). LH then causes the follicle to release an egg (ovulation). The “shell” of the follicle now becomes a corpus luteum which now concentrates on producing increasing amounts of progesterone. Circulating progesterone can rise 10 fold during the week following ovulation. Estrogen production also rises about 6 or 7 days after ovulation. Both these hormones cause the glands in the lining of the uterus to become thick and lush so, if an embryo were to be deposited, it could implant, be nourished and grow. If there is no pregnancy to keep the corpus luteum going it succumbs and there is a decline (so sad) of both estrogen and progesterone. These fallen levels can no longer support the lining of the uterus….it sloughs and hence bleeding occurs. The now low level of estrogen stimulates the pituitary to begin to produce FSH and the entire process begins once more. (Just think of it as waves of rising and falling hormones each month.) Androgens (male hormones) are also produced in the ovaries.
The combination birth control pill basically supplies amounts of synthetic estrogen and progestin which shuts off the pituitary signals to the ovary and hence cyclical hormone production (and ovulation) cease. After menopause, when the follicles in the ovary are “used up” the levels of both estrogen and progesterone will drastically fall. In an abortive effort to get the ovary to produce these hormones, FSH levels rise and continue to remain high for the rest of our postmenopausal lives.
How do the rise and fall of these hormones effect our skin:
- The skin is the largest organ we “own”….There are hormone receptors in the skin and the blood vessels that supply it. Most of what we know regarding to the effects of estrogen on the skin come form studies of what happens to the skin in the absence of estrogen (during menopause).
Here is the estrogen good stuff: It increases skin thickness, decreases collagen breakdown, increases collagen production, increases water binding capacity, increases the ability of blood vessels to dilate, increases elasticity and improves wound healing. This hormone helps prevent sebum (lipid) production, which feeds bacteria and increases the development of pimples. Estrogen also effects fat accumulation under the skin (subcutaneous). Here’s an interesting stat: The thickness of subcutaneous fat has been measured during the menstrual cycle, using ultrasound and MRI. The maximum thickness of subcutaneous fat over the thighs and abdomen has been found to increase during the menstrual cycle (as much as 7.3% in the abdominal region and 4.1% in the thighs). This certainly appears to validate your frequently voiced concerns that you are “get fatter” during your period. Whether this is due to an increase in water retention or changes in the fat cells is not clear.
There is also estrogen bad stuff that can occur in the skin. It increases pigmentation (this is especially evident when combined with sun exposure and use of the estrogen containing birth control pills in sensitive women who then develop pigmentation on the cheeks (chloasma). It also has been associated with decreases cellular-immune response.
Here is what has been noted during the luteal (progesterone) phase of the cycle: There is more sebum production and an increase in skin microbial count….these 2 factors can make you more prone to acne a week before and during your period. The skin is also more sensitive to UVB rays between days 20 and 28 which mean an increase in sun sensitivity.
Effects on the Immune system: This is complicated….estrogens suppress immune response in the cells as well as what we call natural killer activity. (There is a war going on between our bodies and the antigens to which we are exposed. ) Estrogen also increases certain immune proteins in the blood. Because of this increase in antibodies, estrogen may be the significant factor in our high ratio compared to men (20:1) of developing the autoimmune disorder systemic lupus erythematosis (SLE). And if you remember that T cells help us fight infection….well progesterone seems to suppress their formation. (Note T cell numbers remain depressed throughout pregnancy when there is a huge amount of progesterone produced by the placenta….a possible reason for infection severity in pregnant women.)
Effects on Vaginal Discharge: Obviously in the beginning of the cycle there is menstrual blood flow. The average amount is 50 to 100 mL and lasts for 4 to 6 days. As estrogen levels rise the cervix produces more and more mucous and the discharge becomes clear and slippery …sort of like uncooked egg white. (Women as well as their doctors have been checking for this type of mucous to predict fertile days for decades….I even wrote a paper about it in medical school.) As progesterone levels rise after ovulation the mucous becomes stickier. There is a greater glycogen (a form of sugar) content and some women complain of an increase in yeast infections. On the other hand growth of bacteria that don’t like oxygen (bacterial vaginosis) is more likely to become worse during the first 2 week of the cycle.
Effects on overall health: Disorders and distress seem to increase during the luteal phase of our cycles. The list is long: asthma, acne, epilepsy, migraines, myasthenia gravis (severe muscle weakness), certain tachycardias (fast heart beat), sleeping disorders, Reynaud syndrome (where hands and feet become blue from diminished circulation), schizophrenia, glaucoma, insulin resistance and viral diseases. Skin disorders that worsen include acne, rosacea, skin lupus, psoriasis, eczema, vulvar itching, lichen planus and uticaria.
When it comes to estrogen surges and cancer there seems to be an influence on melanoma, certain blood vessel cancers of the skin and of greatest impotence to so many of us, breast cancer. This is a subject for multiple entries and I still wouldn’t be able to give all the final conclusions….But estrogen does stimulate cell divisions in the breast. Many therapies for breast cancer are geared to stopping this estrogen stimulation….these include removal of the ovaries before menopause, inhibition of estrogen production with compounds termed LH agonists and aromatase inhibitors as well as estrogen receptor blockers such as tamoxifen. But pregnancy with its high production of estrogen, especially in younger women is protective! And I have to add this….estrogen and progestin (now termed hormone therapy or HT) may not increase breast cancer for the first few years of use, moreover estrogen therapy given alone (in postmenopausal women who have had a hysterectomy) seems to have little impact on breast cancer risk.
This started out as a simple menstrual cycle primer….sorry that it (and the complexity if our hormonal responses) became more than that. I guess this is the reason that some of us intensely study the effects of female hormones during and after our reproductive years.