Balancing Hormones the Natural Way

Unicity’s Wild Yam Cream
Progesterone is the “Mother of all Hormones”. It is the raw material from which your body makes all other hormones. If your body is overloaded with environmental estrogens and cannot produce enough progesterone to counteract and balance them – dis-ease is the result.
Progesterone is not an “alternative remedy”, it’s an essential need. If your body cannot produce enough progesterone of its own you need to help it by giving it what it needs to protect your health.
Two recent studies of Progesterone supplementation validate what has been contended for the past 12 years: restoring the body’s supply of natural progesterone confers multiple health benefits, including balancing blood sugar levels, promoting normal sleep, reducing anxiety, and stimulating new bone growth.1,2
Beyond preparation for pregnancy, progesterone has a multitude of effects throughout the body, many of which may be attributable to its ability to oppose the action of estrogen. Multiple physical and psychological problems at midlife are often caused by an imbalance between progesterone and estrogen.
The term “Estrogen Dominance” describes the condition of lacking sufficient progesterone to counteract the effects of estrogen. A common misconception is that estrogen
estrogen-dominancedominance results only from extremely high levels of estrogen. To the contrary, this condition also may be caused by normal levels of estrogen and relatively low levels of progesterone, or by low levels of estrogen and extremely low levels of progesterone.
Estrogen levels may be elevated by a number of external influences. Xenoestrogens (foreign estrogens) are among a group of chemicals known to alter hormone levels. Environmental pesticides, including those found on commercially grown fruits and vegetables, are perhaps the primary source of xenoestrogens. Cosmetics, shampoo, and plastics also may contribute to the accumulation of these foreign estrogens.
Progesterone’s many functions in the body include:
  • maintaining the uterine lining and preventing excess tissue buildup
  • inhibiting breast tissue overgrowth
  • increasing metabolism and promoting weight loss
  • balancing blood sugar levels
  • acting as a natural diuretic
  • normalizing blood clotting
  • stimulating the production of new bone
  • enhancing the action of thyroid hormones
  • alleviating depression and reducing anxiety
  • promoting normal sleep patterns
  • preventing cyclical migraines
  • restoring proper cell oxygen levels
  • improving libido.5-16
Symptoms of Progesterone Deficiency/Imbalance
  • Irritability
  • Hypersensitivity
  • Nervousness
  • Restless sleep
  • Headaches/migraines
  • Weight gain
  • Breast tenderness
  • Decreased libido
  • Heavy periods.
Progesterone and the Brain
The brain is highly responsive to progesterone. In fact, progesterone concentrations in the brain have been shown to be 20 times higher than in the blood.2 Insomnia, anxiety, and migraine are just a few of the conditions linked to an imbalance of progesterone and estrogen.19-22
In the brain as elsewhere in the body, progesterone counterbalances the effects of estrogen. Whereas estrogen has an excitatory effect on the brain, progesterone’s effect is calming.9 Clinical and anecdotal experience indicates that women with estrogen dominance sleep restlessly, whereas progesterone replenishment enhances sleep.
It remains unexplained why anxiety disorders are more prevalent in women than in men, and how female hormone-related events (such as menstrual cycle and postpartum) influence the course of anxiety disorders. However, it would appear logical that female hormones and their derivatives play a major role in these observations.23
Several studies have shown progesterone to have anxiolytic (anti-anxiety) effects by acting on gamma-aminobutyric acid (GABA) receptors in the brain.20-22 GABA is an inhibitory neurotransmitter that aids in relaxation and sleep. In the brain, GABA helps balance excitation with inhibition.
A variety of evidence suggests a link between migraine and the female sex hormones. According to the American Migraine Study, 17.6% of females versus only 6% of males in the US currently suffer from severe migraine.25 Many women with migraine, especially those with a history of menstrual migraine, experience an exacerbation of the condition as they approach menopause. During this time, the orderly pattern of estrogen and progesterone secretion is lost.26
In 1953, two English physicians, Drs. Katharina Dalton and Raymond Greene, published the first medical report on premenstrual syndrome (PMS). Dr. Dalton observed that progesterone injections relieved her own menstrual migraine headaches. Dr. Dalton then injected progesterone into other women and found that their PMS was cured.11 Hormone replacement with estrogen exacerbates migraine, and oral contraceptives can change the character and frequency of migraine.27
Pregnancy, Infertility and Miscarriages
Adequate levels of progesterone are vital to pregnancy. If you are estrogen dominant and progesterone deficient, supplementing with natural progesterone can help you fall pregnant
and stay pregnant.You could actually be fertile whilst appearing to suffer from infertility! One of the most common causes of apparent infertility is a lack of progesterone during the second half of the month – known as the defective luteal phase.
For pregnancy to occur estrogen first builds the lining of the uterus. Then after ovulation, progesterone thickens the uterus lining ready for implantation of the fertilized egg. Often conception does take place but due to the lack of progesterone the lining of the uterus is not ready for the egg and miscarriage occurs as early as the next period. The egg just had nowhere to implant itself! Adequate levels of progesterone are therefore:
essential for successful pregnancy
Once pregnant, if progesterone production is too low during the weeks following fertilization – a miscarriage can result.
Another cause of infertility is the fact that some woman do not ovulate every month. This can be the result of too much estrogen, particularly the xeno-estrogens such as DDT (pesticides).
Progesterone and Osteoporosis
  • With osteoporosis reaching epidemic levels in the West, and the prediction that 1 in 3 women and 1 in 8 men are likely to get it, it is not surprising that this has become a growing concern.
Bone is a very metabolically active tissue, and bone remodeling continues throughout life. The remodeling process is an active coupling of bone formation and bone resorption. Bone loss occurs when the cellular events of bone resorption are quantitatively greater than the events of bone formation.
Conventional medicine widely attributes osteoporosis to a decline in estrogen. Before the onset of menopause, however, luteal levels of progesterone decline, whereas levels of estrogen, lutenizing hormone, follicle stimulating hormone, and other reproductive hormones remain intact. In addition, we know that bone loss begins in women well before menopause.
In fact, a woman attains her peak bone density at approximately 30 years of age, after which she begins to lose bone at a rate of about 1-1.5% per year.9 Countless women who use estrogen therapy and consume the proper nutrients still have disappointing bone density test results. These facts raise an interesting question: is the decline in estrogen responsible for bone loss, or is progesterone involved, possibly even more so than estrogen? The two types of bone-regulating cells are osteoclasts and osteoblasts. Osteoclasts function to dissolve older bone, leaving tiny unfilled spaces behind. Osteoblasts are then able to move into these spaces to produce new bone. Like all living cells, osteoblasts and osteoclasts require hormonal guidance to function properly.
Estrogen is able to help slow bone loss by curbing the activity of bone-dissolving osteoclasts.31,32 On the other hand, osteoblasts depend primarily on progesterone and testosterone to facilitate the building of new bone. In the absence of these hormones, osteoblasts and osteoclasts cease to function properly, and rapid deterioration of bone occurs.
Natural progesterone stimulates the new bone formation required to prevent and reverse osteoporosis.7 Progesterone also appears to increase levels of insulin-like growth factor 1, which promotes bone formation.33 It remains uncertain whether progesterone or estrogen plays a more prominent role in bone remodeling. An optimal balance of both hormones appears to be most efficient in preventing and treating osteoporosis.
Progesterone and Cancer
Disturbances in gonadal hormones have been associated with an increased risk of both breast and endometrial cancers. Most controlled studies and observational studies in the past five years suggest that the addition of synthetic progestins to synthetic estrogen in hormone replacement therapy, particularly in a continuous combined regimen, increases breast cancer risk compared to synthetic estrogen alone.1
By contrast, recent studies suggest that the addition of natural progesterone does not affect breast cancer risk.1,2 Whereas estrogen is pro-proliferative, causing the cells in the breast and uterus to multiply, progesterone does not promote proliferation of these tissues.One of the most sign In fact, a large base of evidence suggests that progesterone is a protective agent against, as well as a potential adjunctive treatment for, breast and endometrial cancers.34-44
Significant studies of the relationship between low levels of natural progesterone and increased breast cancer risk was published in the American Journal of Epidemiology in 1981.
  • The study followed 1,083 women with a history of difficulty becoming pregnant for periods ranging from 13 to 33 years. The researchers found that infertile women who demonstrated a progesterone deficiency had a premenopausal breast cancer risk that was 540% greater than that of women whose infertility was due to non-hormonal causes. Furthermore, the women with a progesterone deficiency had a 1,000% greater chance of death from all types of cancer.34
  • In a study conducted at the National Taiwan University Hospital, researchers showed that transdermal estradiol increased breast cell proliferation by 230%, while transdermal progesterone decreased cell proliferation by over 400%.6 A combination of estradiol and progesterone cream was able to maintain the normal proliferation rate.
Serum progesterone levels at the time of breast cancer surgery influence survival rates, according to a 1996 study published in the British Journal of Cancer.
  • Women who had progesterone levels of 4 ng/mL or greater at the time of breast cancer surgery had significantly better survival rates at 18 years than those with lower serum levels of progesterone at the time of surgery. In women with higher progesterone levels at the time of surgery, approximately 65% were alive 18 years later, whereas only 35% of the women with low progesterone levels survived 18 years.45
Conventional estrogen replacement therapy with synthetic estrogens increases the incidenceof endometrial (uterine lining) abnormalities, including cancer.37 However, co-administration of progesterone counteracts this effect.36-44 Women are also becoming increasingly aware of other serious health conditions that may result from an imbalance of their gonadal hormones.
  • Some scientists believe that conditions such as ovarian cysts, uterine fibroids, fibrocystic breast disease, and cervical erosions may stem from an imbalance between progesterone and estrogen.12
Progesterone and Hysterectomy
Hysterectomy is the surgical removal of the uterus, which is sometimes performed in conjunction with an oophorectomy or ovariectomy, which is the surgical removal of the ovaries.
  • Doctors often perform a hysterectomy to alleviate patient discomforts associated with conditions such as uterine fibroids, endometriosis, and heavy menses. These conditions, however, are often related to a relative dominance of estrogen.12
Removal of the uterus does not correct the underlying imbalance that may have contributed to these conditions in the first place.
Many medical professionals believe that once the uterus has been removed, there is no need to supplement with progesterone. Clinical experience and a review of the scientific literature, however, make it is clear that unopposed estrogen therapy can lead to many undesirable health conditions.
  • When women are young, they have optimal levels of all the steroid hormones, not just estrogen. Replacing only estrogen after a complete hysterectomy is a sure-fire way to increase existing estrogen dominance. Whether a woman has a uterus or not, research suggests that estrogen replacement therapy should not be given without natural progesterone.
Natural progesterone therapy facilitates normal thyroid hormone action. Dr. Lee has successfully treated people with a hypothyroid (under active thyroid) condition as well as people with hyperthyroidism (excessive production of the thyroid gland) and Hashimoto’s thyroiditis with natural progesterone therapy.
  • Low thyroid activity causes low energy levels, cold intolerance and weight gain.
  • Excess thyroid activity induces higher energy levels, feeling too warm and weight loss.
  • Estrogen, progesterone and thyroid hormones are complementary. Estrogen tells the body to turn food into fat while thyroid and progesterone hormones tell the body to burn fat for energy. Thyroid hormone and estrogen balance each other’s effects.
  • If there is unopposed estrogen or estrogen dominance the thyroid may be unable to keep up.
Progesterone and Men
Typically thought of as a female hormone, progesterone can also be an invaluable tool in hormone modulation in men. Progesterone is manufactured in men by the adrenal glands and testes. Just as estrogen dominance can severely affect the quality of life for women, excess estrogen can be equally detrimental to men.
Elevated estrogen in men has been linked to gynecomastia (breast enlargement in men), decreased sexual function, weight gain, and prostate enlargement.46-48
Benign prostatic hyperplasia seems to be related to long-term exposure of the prostate gland to the strong androgen dihydrotestosterone and possibly to estrogens. In fact, the late Dr. John R. Lee, considered a pioneer in natural progesterone therapy, believed that excessive exposure to estrogen was a primary cause of prostate enlargement and prostate cancer.
In addition to counterbalancing the negative aspects of estrogen, progesterone may also inhibit 5-alpha-reductase, the enzyme that converts testosterone to dihydrotestosterone.49
Here is a list of some of the benefits you may experience once you begin to balance a progesterone deficiency and curb estrogen dominance.
  • Natural progesterone is a natural antidepressant.
  • Natural progesterone restores the sex drive.
  • Relief from PMS symptoms that you’ve always just had to “live with.” Natural progesterone is effective in treating PMS because when estrogen is not balanced by progesterone, it produces weight gain, headaches, bad temper, chronic fatigue, breast tenderness and a loss of interest in sex – all of which are part of the clinically recognized symptoms of pre-menstrual syndrome.
  • Relief from menstrual cramping. Many women have found relief within 20 minutes of rubbing natural progesterone cream onto their stomachs.
  • Hot Flashes/Night Sweats
  • Mood Swings
  • Insomnia
Pre-Menopausal Women benefit from natural progesterone cream which can help balance the symptoms often associated with uterine fibroids, endometriosis and bring relief from irritability, bloating, water retention, weight gain and pelvic pain and excess bleeding.
For women entering menopause, natural progesterone cream helps the decreasing supplies of progesterone which cause hormonal imbalances, producing hot flashes, mood swings, urinary incontinence, hair loss, vaginal dryness, poor concentration, uterine fibroids and an overall decline in health.
You get relief from the normal symptoms of menopause which include hot flushes, night sweats, insomnia, restlessness, vaginal dryness and mood swings. Menopause is not an estrogen deficiency disease. Estrogen levels fall by 40 – 60% during menopause, but progesterone levels often fall to zero or close to zero, which means the symptoms experienced by menopausal women are actually the symptoms of estrogen dominance!
The most effective and safe treatment of menopause symptoms is to balance off the excess estrogens in the body with natural progesterone. Studies indicate that Natural progesterone cream shrinks fibroids, curbs hot flashes and hormonal imbalances associated with menopause and the absence or decline in progesterone.
  • In 1999 trials at St. Luke’s Hospital in Bethlehem, Pennsylvania, bioidentical progesterone reduced or eliminated hot flashes in 83 percent of the healthy postmenopausal women tested. Other clinical trials have shown significant reduction in uterine fibroids, weight loss, a reversal of premenstrual dysphoric disorder and endometriosis to be not only significantly improved but reversed with the use of bioidentical progesterone.
“Natural progesterone helps to reduce symptoms of both bloating and cramping”
  • Because it normalizes blood sugar levels natural progesterone also alleviates cravings and binge-eating and therefore further helps to reduce weight.
“It is a natural diuretic helping to release excess water that is being stored in the body.’
Questions and Answers.
Q: What is progesterone?
A: Progesterone is a steroid hormone made by the corpus luteum of the ovary at ovulation, and in smaller amounts by the adrenal glands. Progesterone is manufactured in the body from the steroid hormone pregnenolone, and is a precursor to most of the other steroid hormones, including cortisol, androstenedione, the estrogens and testosterone.In a normally cycling female, the corpus luteum produces 20 to 30 mg of progesterone daily during the luteal phase of the menstrual cycle.
Q: Why do women need progesterone?
A: Progesterone is needed in hormone replacement therapy for menopausal women for many reasons, but one of its most important roles is to balance or oppose the effects of estrogen. Unopposed estrogen creates a strong risk for breast cancer and reproductive cancers. Estrogen levels drop only 40-60% at menopause, which is just enough to stop the menstrual cycle. But progesterone levels may drop to near zero in some women. Because progesterone is the precursor to so many other steroid hormones, its use can greatly enhance overall hormone balance after menopause. Progesterone also stimulates bone-building and thus helps protect against osteoporosis.
Q: What is estrogen dominance?
A: Dr. Lee has coined the term “estrogen dominance,” to describe what happens when the normal ratio or balance of estrogen to progesterone is changed by excess estrogen or inadequate progesterone. Estrogen is a potent and potentially dangerous hormone when not balanced by adequate progesterone. Both women who have suffered from PMS and women who have suffered from menopausal symptoms, will recognize the hallmark symptoms of estrogen dominance: weight gain, bloating, mood swings, irritability, tender breasts, headaches, fatigue, depression, hypoglycemia, uterine fibroids, endometriosis, and fibrocystic breasts. Estrogen dominance is known to cause and/or contribute to cancer of the breast, ovary, endometrium (uterus), and prostate.
Q: Why would a premenopausal woman need progesterone cream?
A: In the ten to fifteen years before menopause, many women regularly have anovulatory cycles in which they make enough estrogen to create menstruation, but they don’t make any progesterone, thus setting the stage for estrogen dominance. Using progesterone cream during anovulatory months can help prevent the symptoms of PMS. We now know that PMS can occur despite normal progesterone levels when stress is present. Stress increases cortisol production; cortisol blockades (or competes for) progesterone receptors. Additional progesterone is required to overcome this blockade, and stress management is important.
Q: Why not just use the progestin Provera as prescribed by most doctors?
A: Progesterone is preferable to the synthetic progestins such as Provera, because it is natural to the body and has no undesirable side effects when used as directed. If you have any doubts about how different progesterone is from the progestins, remember that the placenta produces 300-400 mg of progesterone daily during the last few months of pregnancy, so we know that such levels are safe for the developing baby. But progestins, even at fractions of this dose, can cause birth defects. The progestins also cause many other side effects, including partial loss of vision, breast cancer in test dogs, an increased risk of strokes, fluid retention, migraine headaches, asthma, cardiac irregularities and depression.
Q: Wouldn’t it be easier to just take a progesterone pill?
A: Dr. Lee recommends the transdermal cream rather than oral progesterone, because some 80% to 90% of the oral dose is lost through the liver. Thus, at least 200 to 400 mg daily is needed orally to achieve a physiologic dose of 15 to 24 mg daily. Such high doses create undesirable metabolites and unnecessarily overload the liver.
Q: Do Progesterone Creams work better than taking an oral progesterone pill?
A: “Transdermal” progesterone means that it is applied to the skin and passes into the subcutaneous fat, the layer of fat just below the skin. From there it enters the bloodstream. This is the only dosing method that approximates the natural, gradual physiological release of the hormone.There are a number of problems with oral progesterone, including the need to take large amounts of it because of poor gastrointestinal absorption, the tendency for it to be released in surges, and the production of metabolites (substances formed by metabolic processes) that don’t function like true progesterone.
Q: Where should I put the progesterone cream?
A: Because progesterone is very fat-soluble, it is easily absorbed through the skin. From subcutaneous fat, progesterone is absorbed into capillary blood. Thus absorption is best at all the skin sites where people blush: face, neck, chest, breasts, inner arms and palms of the hands.
Q: What is the right dose of progesterone for me?
A: It is important that any progesterone cream you buy have at least 400 mg of progesterone per ounce. An application of 1/8 tsp contains about 10 mg; 1/4 tsp is about 21 mg; and 1/2 tsp is about 42 mg.It is really up to you to experiment with what is the right amount for you, by the measure of how well you feel, and depending on your symptoms or your personal goals, but here are some guidelines:
A usual dose for premenopausal women would be 15 to 24 mg (slightly less than or slightly more than 1/4 tsp) per day for 14 days before expected menses, stopping a day or two before menses begins.
A dose that works well for many postmenopausal women is 15 mg (slightly less than 1/4 tsp) per day for 25 days each month, following a consistent monthly pattern.
Q: Where can I get more information on progesterone and natural hormone balance?
A: For a detailed explanation of women’s hormone balance issues, a hormone balance program, as well as detailed descriptions of how to use natural progesterone, the following books by John R. Lee, M.D. are recommended:
  • What Your Doctor May Not Tell You About Menopause ~ by Doctor John Lee
  • What Your Doctor May Not Tell You About Pre-Menopause ~ by Doctor Lee
Author: Darlene Long
1. Campagnoli C, Clavel-Chapelon F, Kaaks R, Peris C, Berrino F. Progestins and progesterone in hormone replacement therapy and the risk of breast cancer. J Steroid Biochem Mol Biol. 2005 Jul;96(2):95-108.2. Stein DG. The case for progesterone. Ann NY Acad Sci. 2005 Jun;1052:152-69.3. Yen SSC. Endocrine-Metabolic Alterations in Pregnancy. Philadelphia, PA: WB Saunders Co.; 1991:936-981.4. Andersen CY. Concentrations of free oestradiol and progesterone in human preovulatory follicular fluid. Hum Reprod. 1991 Mar;6(3):359-64.5. Clarke CL, Sutherland RL. Progestin regulation of cellular proliferation. Endocr Rev. 1990 May;11(2):266-301.6. Chang KJ, Lee TT, Linares-Cruz G, Fournier S, de Lignieres B. Influences of percutaneous administration of estradiol and progesterone on human breast epithelial cell cycle in vivo. Fertil Steril. 1995 Apr;63(4):785-91.7. Heersche JN, Bellows CG, Ishida Y. The decrease in bone mass associated with aging and menopause. J Prosthet Dent. 1998 Jan;79(1):14-6.8. Dzugan SA, Smith RA. The simultaneous restoration of neurohormonal and metabolic integrity as a very promising method of migraine management. Bull Urg Rec Med. 2003;4(4):622-8.9. Hotze SF. Hormones, Health, and Happiness. Houston, TX: Forrest Publishing; 2005.10. Akande EO. Plasma concentration of gonadotrophins, oestrogen and progesterone in hypothyroid women. Br J Obstet Gynaecol. 1975 Jul;82(7):552-6.11. Dalton, K. The Premenstrual Syndrome and Progesterone Therapy. Chicago, IL: Year Book Medical Publishers; 1977.12. Lee JR, Zava D, Hopkins V. What Your Doctor May Not Tell You About Breast Cancer. New York, NY: Warner Books; 2002.13. Huber J. Estrogen substitution therapy in climacteric: should progesterone be omitted in hysterectomized women? Geburtshilfe Frauenheilkd. 1991 Apr;51(4):257-61.14. Sumino H, Ichikawa S, Itoh H, et al. Hormone replacement therapy decreases insulin resistance and lipid metabolism in Japanese postmenopausal women with impaired and normal glucose tolerance. Horm Res. 2003;60(3):134-42.15. Kanaya A, Herrington D, Vittinghoff E, et al. Glycemic effects of postmenopausal hormone therapy: the heart and estrogen/progestin replacement study: a randomized, double-blind, placebo-controlled trial. Ann Intern Med. 2003 Jan 7;138(1):1-9.16. Chmouliovsky L, Habicht F, James RW, Lehmann T, Campana A, Golay A. Beneficial effect of hormone replacement therapy on weight loss in obese menopausal women. Maturitas. 1999 Aug 16;32(3):147-53.17. Available at:…. Accessed January 10, 2005.18. Simoncini T, Mannella P, Fornari L, et al. Differential signal transduction of progesterone and medroxyprogesterone acetate in human endothelial cells. Endocrinology. 2004 Dec; 145(12):5745-56.19. Beckham JC, Krug LM, Penzien DB, et al. The relationship of ovarian steroids, headache activity and menstrual distress: a pilot study with female migraineurs. Headache. 1992 Jun;32(6):292-7.20. Smith SS, Waterhouse BD, Chapin JK, Woodward DJ. Progesterone alters GABA and glutamate responsiveness: a possible mechanism for its anxiolytic action. Brain Res. 1987 Jan 6;400(2):353-9.21. Gulinello M, Smith SS. Anxiogenic effects of neurosteroid exposure: sex differences and altered GABAA receptor pharmacology in adult rats. J Pharmacol Exp Ther. 2003 May;305(2):541-8.22. Rupprecht R. Neuroactive steroids: mechanisms of action and neuropsychopharmacological properties. Psychoneuroendocrinology. 2003 Feb;28(2):139-68.23. Le Melledo JM, Baker G. Role of progesterone and other neuroactive steroids in anxiety disorders. Expert Rev Neurother. 2004 Sep;4(5):851-60.24. Hsu FC, Smith SS. Progesterone withdrawal reduces paired-pulse inhibition in rat hippocampus: dependence on GABA(A) receptor alpha4 subunit upregulation. J Neurophysiol. 2003 Jan;89(1):186-98.25. Lipton RB, Stewart WF. Migraine in the United States: a review of epidemiology and health care use. Neurology. 1993 Jun;43(6 Suppl 3):S6-10.26. Fettes I. Migraine in the menopause. Neurology. 1999;53(4 Suppl 1):S29-33.27. Silberstein SD, Merriam GR. Sex hormones and headache. J Pain Symptom Manage. 1993 Feb;8(2):98-114.28. Li W, Zheng T, Altura BM, Altura BT. Sex steroid hormones exert biphasic effects on cytosolic magnesium ions in cerebral vascular smooth muscle cells: possible relationships to migraine frequency in premenstrual syndromes and stroke incidence. Brain Res Bull. 2001 Jan 1;54(1):83-9.29. Tolsa JF, Gao Y, Raj JU. Developmental change in magnesium sulfate-induced relaxation of rabbit pulmonary arteries. J Appl Physiol. 1999 Nov;87(5):1589-94.30. O’Shaughnessy A, Muneyyirci-Delale O, Nacharaju VL, et al. Circulating divalent cations in asymptomatic ovarian hyperstimulation and in vitro fertilization patients. Gynecol Obstet Invest. 2001;52(4):237-42.31. Turner RT, Colvard DS, Spelsberg TC. Estrogen inhibition of periosteal bone formation in rat long bones: down-regulation of gene expression for bone matrix proteins. Endocrinology. 1990 Sep;127(3):1346-51.32. Turner RT, Backup P, Sherman PJ, Hill E, Evans GL, Spelsberg TC. Mechanism of action of estrogen on intramembranous bone formation: regulation of osteoblast differentiation and activity. Endocrinology. 1992 Aug;131(2):883-9.33. Barengolts EI, Kouznetsova T, Segalene A, et al. Effects of progesterone on serum levels of IGF-1 and on femur IGF-1 mRNA in ovariectomized rats. J Bone Miner Res. 1996 Oct;11(10):1406-12.34. Cowan LD, Gordis L, Tonascia JA, Jones GS. Breast cancer incidence in women with a history of progesterone deficiency. Am J Epidemiol. 1981 Aug;114(2):209-17.35. Formby B, Wiley TS. Progesterone inhibits growth and induces apoptosis in breast cancer cells: inverse effects on Bcl-2 and p53. Ann Clin Lab Sci. 1998 Nov-Dec;28(6):360-9.36. Creasman WT. Hormone replacement therapy after cancers. Curr Opin Oncol. 2005 Sep;17(5):493-9.37. Medina RA, Meneses AM, Vera JC, et al. Differential regulation of glucose transporter expression by estrogen and progesterone in Ishikawa endometrial cancer cells. J Endocrinol. 2004 Sep;182(3):467-78.38. De Vivo I, Huggins GS, Hankinson SE, et al. A functional polymorphism in the promoter of the progesterone receptor gene associated with endometrial cancer risk. Proc Natl Acad Sci USA. 2002 Sep 17;99(19):12263-8.39. La Vecchia C, Brinton LA, McTiernan A. Cancer risk in menopausal women. Best Pract Res Clin Obstet Gynaecol. 2002 Jun;16(3):293-307.40. Southcott BM. Carcinoma of the endometrium. Drugs. 2001;61(10):1395-405.41. Mahavni V, Sood AK. Hormone replacement therapy and cancer risk. Curr Opin Oncol. 2001 Sep;13(5):384-9.42. Beresford SA, Weiss NS, Voigt LF, McKnight B. Risk of endometrial cancer in relation to use of oestrogen combined with cyclic progestagen therapy in postmenopausal women. Lancet. 1997 Feb 15;349(9050):458-61.43. Ravn SH, Rosenberg J, Bostofte E. Postmenopausal hormone replacement therapy—clinical implications. Eur J Obstet Gynecol Reprod Biol. 1994 Feb;53(2):81-93.44. Samsioe G. The endometrium: effects of estrogen and estrogen-progestogen replacement therapy. Int J Fertil Menopausal Stud. 1994;39 Suppl 2:84-92.45. Mohr PE, Wang DY, Gregory WM, Richards MA, Fentiman IS. Serum progesterone and prognosis in operable breast cancer. Br J Cancer. 1996 Jun;73(12):1552-5.46. Sodi R, Fikri R, Diver M, Ranganath L, Vora J. Testosterone replacement-induced hyperprolactinaemia: case report and review of the literature. Ann Clin Biochem. 2005 Mar;42(Pt 2):153-9.47. Plourde PV, Reiter EO, Jou HC, et al. Safety and efficacy of anastrozole for the treatment of pubertal gynecomastia: a randomized, double-blind, placebo-controlled trial. J Clin Endocrinol Metab. 2004 Sep;89(9):4428-33.48. Comhaire F, Mahmoud A. Preventing diseases of the prostate in the elderly using hormones and nutriceuticals. Aging Male. 2004 Jun;7(2):155-69.49. Tilakaratne A, Soory M. Effects of the anti-androgen finasteride on 5 alpha-reduction of androgens in the presence of progesterone in human gingival fibroblasts: modulatory actions of the alkaline phosphatase inhibitor levamisole. J Periodontal Res. 2000 Aug;35(4):179-85.50. Available at:…. Accessed October 4, 2005.51. Apgar BS, Greenberg G. Using progestins in clinical practice. Am Fam Physician. 2000 Oct 15;62(8):1839-50.