Susan Merenstein, Pharmacist/Owner

(412) 586-4678


Progesterone - An Amazing Hormone

What is the difference between natural and synthetic Progesterone?

Progesterone was first crystallized in 1934, and today is available from plant sources. “Natural” micronized progesterone (also termed USP Progesterone) refers to a single molecular structure that is “bio-identical” and is an exact chemical duplicate of the progesterone women produce in their ovaries. Synthetic “progestogens” or “progestins” mimic the action of the progesterone closely enough to bind to progesterone receptor sites, but the body does not respond in the same way. As such, synthetic progestins are not recommended for use during pregnancy; pregnancy requires progesterone. Synthetic progestins will not increase the serum or salivary levels of progesterone. Studies have shown that progestogen actually reduces the level of progesterone in the blood stream by blocking the process of progesterone production. In contrast, research studies show that topical (skin) applications of natural progesterone may increase salivary and serum levels of progesterone. Natural progesterone is available through topical applications, oral micronized progesterone, injectable progesterone, vaginal gel, suppositories, and sublingual drops or troches.

Are there side effects with natural Progesterone?

“Natural” BIOIDENTICAL progesterone combines with progesterone receptor sites throughout the body and causes biological effects without many of the undesirable effects that are seen with the synthetic forms (i.e., Provera). A small number of sensitive women may experience transient lightheadedness or drowsiness due to progesterone’s calming effect on the central nervous system. There are no long-term adverse effects noted for supplemental progesterone in amounts that replicate physiological levels of progesterone in the body.

How does oral Progesterone work?

The oral route of progesterone administration has long been thought to be impractical due to poor absorption and short biological half-life. More recent reports* confirm that significant serum progesterone levels can be achieved with new modification in the preparation of progesterone for oral administration, including micronization and dissolution in oils consisting principally of long-chain fatty acids. One of the only disadvantages of natural progesterone is that it is short-acting and to maintain adequate blood levels it may need be taken more frequently. *” Absorption of Oral Progesterone is Influenced by Vehicle and Particle size,” Joel T. Hargrove, MD,Wayne S. Maxon, MD, and Anne Colston Wentz, MD, American Journal of Obstetrics and Gynecology, October 1989.

What is Progesterone’s Role in the body?

  • Prepare the endometrium for implantation of the fertilized ovum
  • Ensure survival of the fetus in the uterus
  • Prevent water retention
  • Help use fat for energy at the cellular level
  • Acts as a natural antidepressant
  • Create a calming effect on the body
  • Help restore regular sleep patterns
  • Help keep insulin release in check and maintain even blood sugar levels
  • Prevent overgrowth of the endometrium
  • Prevent breast tissue overgrowth
  • Maintain sex drive
  • Maintain normal blood clotting parameters
  • Protect against fibrocystic breasts

Do I need Progesterone if I have had my uterus removed?

If the intent of using progesterone is merely to slough off endometrial tissue, then progesterone would not be necessary. But progesterone is needed by the body to balance estrogen’s effect on the breast and other body sites and to prevent ESTROGEN DOMINANCE, so perhaps it should be considered. A recent study* presented by Mayo Clinic researchers, determined that there were impressive significant improvements in quality-of-life issues such as hot flashes, menstrual problems, sexual function, physical complaints, anxiety and depression with natural progesterone. These are important issues for women with and without a uterus.

*” Comparison of Regimens Containing Oral Micronized Progesterone....,” Lorraine A. Fitzpatrick, MD, Cindy Pace, BS, and Brinda Wiita, PhD, Journal of Women’s Health & Gender-Based Medicine, May 2000; Vol 9, No.4;

pp. 381-387.

Is natural Progesterone taken orally destroyed by stomach acid?

The powder form of natural progesterone is destroyed by stomach acid. But, when compounded in an oil base, the progesterone is so firmly held by the oil base that it is actually absorbed through the lymphatic system first, thereby allowing a few passes through the body before being cleared via the liver. *

*” Absorption of Oral Progesterone is Influenced by Vehicle and Particle size,” Joel T. Hargrove, MD, Wayne S. Maxon, MD, and Anne Colston Wentz, MD, American Journal of Obstetrics and Gynecology, October 1989

What’s the difference between wild yam and Progesterone?

Wild yam, Dioscorea barbasco, is an herb that has been used historically in herbal medicine for women’s health. Some of the actions of wild yam include smooth muscle relaxation and a mild diuretic effect. Contrary to some information provided by companies producing wild yam products, wild yam does not convert into progesterone in the body. This conversion can only occur in a laboratory setting. The body may absorb wild yam extract through the skin, which may in turn have some effect on menopausal symptoms, yet research on both oral and topical applications of wild yam extract demonstrate no change in progesterone levels in the body.

Does Progesterone help raise estrogen levels?

There is no evidence that supplementing with natural progesterone will raise estrogen levels in the body. From salivary test results we know that women using natural progesterone cream do not by and large see an increase in their estrogen levels. We do know that progesterone and estrogen, like many of the hormones in the body, work synergistically. The presence of progesterone sensitizes estrogen receptors in the body, making circulating estrogen levels work better without changing the actual levels of estrogen. Progesterone performs this role with other hormones as well. Since women’s bodies have the ability to produce some estrogens after menopause, many women find that supplementation of progesterone is enough, or at least part of the picture for addressing symptoms. For women who are very thin, who have had hysterectomies at a younger age, or have certain risk factors, like high cholesterol or heightened bone loss, some form of estrogen or phytoestrogens may be necessary to completely fulfill their bodies’ needs. Keep in mind that the balance of the different hormones is important and should by tailored specifically to the individual.

What is natural Progesterone’s role in PMS?

There are several different types of PMS recognized. Women who suffer from certain kinds of PMS may have a relative excess of estrogen, caused by either a low progesterone level or too much estrogen in relation to progesterone. This condition is often called “estrogen dominance”. Common symptoms of estrogen dominance include breast tenderness, bloating, headache, irritability and mood swings. If your PMS is a result of excess estrogen or insufficient progesterone, then supplementing progesterone during the second half of your cycle (from the time of ovulation until menses) may help reduce PMS symptoms.

What is natural Progesterone’s role in cardiovascular health?

Natural progesterone may have a protective effect on the heart. Recent research showed that natural progesterone helped reduce spasms of the coronary arteries. Blood vessel occlusion by cholesterol plaques combined with vasoconstriction can severely restrict blood flow to the heart, resulting in a “heart attack”. In a study by Miyagawa, et al, progesterone plus estradiol was protective against vasospasm, whereas estradiol plus medroxyprogesterone acetate (a synthetic progestin) allowed vasospasm, concluding that medroxyprogesterone increased the risk of coronary vasospasm, while natural progesterone did not. (Miyagawa K, Rosch J, Stanczyk F, and Hermsmeyre K: Medroxyprogesterone interferes with ovarian steroid protection against coronary vasospasm. Nature Medicine, Vol. 3, No. 3, 324-327.)

What is the difference between Progesterone made by the ovaries and Progestins?

Will using natural Progesterone with oral birth control pills alter their effectiveness?

Using natural progesterone should not alter the effectiveness of oral birth control pills providing you keep taking the oral birth control pills as prescribed. Birth control pills may be progestin only pills (synthetic progestins), or a combination of progestins and estrogen. Adding supplemental progesterone will only increase the pregestational effect in the body.

Does Progesterone affect hair loss in women?

When progesterone levels fall as a result of ovarian follicle failure (lack of ovulation), the body responds by increasing its production of the adrenal cortical steroid, androstenedione, an alternative precursor for the production of other adrenal cortical hormones. Androstenedione conveys some androgenic (male-like) properties, in this case, male pattern hair loss. When progesterone levels are raised by progesterone supplementation (oral or topical), the androstenedione level will gradually fall, and normal hair growth will eventually resume. Since hair growth is a slow process, it may take four to six months for the effects to become apparent.

What is Progesterone’s role in preventing Breast Cancer?

The actual causes of breast cancer are still largely unknown, but most authorities agree that estrogen is at least a promoter of breast cancer. In industrialized countries, it has become epidemic that progesterone deficiency and estrogen dominance among women occur during their mid-thirties. Estrogen dominance increases the risk of breast cancer. To prevent breast cancer, it is wise to follow a plant-based diet to avoid xenoestrogens in red meat and dairy foods, and to supplement with natural progesterone. Avoid synthetic progestins; they may increase breast cancer risk, whereas there is strong evidence that natural progesterone protects against breast cancer. There are at least 4 studies in the medical literature associating a deficiency of progesterone with an increased risk of breast cancer. The medical literature also includes several interesting studies showing that young women who undergo mastectomies for breast cancer have a much better survival rate and recurrence-free prognosis when the surgery is performed during the luteal phase of the menstrual cycle. This is the time of the month when the body produces the most progesterone. Because of the potential for saving lives and preventing recurrences, this area of research should be vigorously pursued. The cancer research community does women a great injustice by continuing to ignore natural hormones. The financial interests of companies should not take priority over the welfare of half the population. The restoration of natural hormonal balance in the body is missing from conventional HRT.