Progesterone is a naturally occurring steroid hormone essential for the female reproductive system and overall health. It is primarily produced in the ovaries, though the adrenal glands also contribute to its levels. Progesterone regulates the menstrual cycle, supports early pregnancy by preparing the uterine lining, and works to balance the effects of estrogen. When hormone levels fluctuate or decline, the body’s natural balance can be disrupted. Using progesterone in a transdermal cream format allows the hormone to be absorbed directly through the skin into the bloodstream, supplementing the body’s natural supply when levels are low or unbalanced.
The Difference Between Progesterone and Progestins
It is important to distinguish between progesterone and progestins, as they are not the same substance. Progesterone cream typically contains bioidentical progesterone, which is chemically and molecularly identical to the hormone the human body produces. This natural form is often derived from plant sources like yams or soy and processed into the exact molecular structure of human progesterone.
Progestins, in contrast, are synthetic compounds designed to mimic some of progesterone’s actions. Pharmaceutical companies developed these because natural progesterone is poorly absorbed when taken orally and is quickly metabolized. However, because progestins have different chemical structures, they interact with hormone receptors differently than natural progesterone. These synthetic versions are commonly found in oral contraceptives and traditional hormone replacement therapy, and they may carry different effects and side-effect profiles compared to the bioidentical hormone.
Managing Symptoms of Hormone Decline
The most frequent reason for using progesterone cream is to manage symptoms arising from declining or unbalanced hormones, particularly during perimenopause and menopause. Progesterone works to counteract the proliferative effects of estrogen, which is important for women who still have a uterus. When estrogen is dominant or unopposed, it can cause the uterine lining to thicken, a condition progesterone helps regulate.
The decline in progesterone levels contributes to uncomfortable symptoms, including hot flashes and night sweats. Supplementing with progesterone cream can help reduce the frequency and intensity of these vasomotor symptoms. Progesterone also has a calming effect on the nervous system. The hormone influences neurotransmitters in the brain, which may help alleviate mood disturbances, such as anxiety and irritability, often associated with hormonal shifts.
Progesterone is also recognized for supporting restorative sleep. Studies indicate that when used as a supplement, it can improve sleep quality, which is frequently disrupted during the menopausal transition. This improvement is thought to be due to its sedative metabolites, although these effects are often more strongly linked to oral forms metabolized by the liver. Transdermal application offers a non-oral option to help manage the physical and emotional changes that accompany hormone decline and maintain steady hormone levels.
Application Methods and Absorption
Progesterone cream delivers the hormone through transdermal absorption, meaning it passes through the skin and enters the systemic circulation. This method bypasses the digestive system and initial liver metabolism, which significantly reduces the potency of hormones taken orally. The effectiveness depends on the application site, as areas with thinner skin and good blood flow allow for efficient absorption.
Common application sites include the inner arms, inner thighs, chest, neck, and behind the knees. It is recommended to rotate application sites with each use to prevent the saturation of local skin receptors, which can decrease absorption efficiency over time. Some practitioners advise applying the cream to areas above the navel to ensure the hormone enters the systemic circulation before being processed by the liver.
The frequency and duration of use depend on a woman’s hormonal status and whether she is still menstruating. Women who are pre- or perimenopausal typically follow a cyclical dosing schedule. This involves using the cream for two weeks during the second half of the cycle, then stopping to allow for a period, which mimics the body’s natural hormone production pattern. Postmenopausal women, or those on continuous estrogen therapy, typically use the cream every day of the month to provide consistent support.
Other Common Uses for Progesterone Cream
Beyond menopausal symptom management, progesterone cream is used for specific issues related to hormonal balance. For women with regular cycles, it can help relieve symptoms of premenstrual syndrome (PMS). PMS symptoms such as bloating, breast tenderness, and mood swings are often linked to a hormonal imbalance in the latter half of the cycle. Supplementing with progesterone during the premenstrual phase may help correct this imbalance and reduce symptom severity.
Another application is the support for bone health. Progesterone stimulates the formation of new bone tissue, and low levels are associated with decreased bone mineral density. Some evidence suggests that progesterone supplementation, including transdermal cream, may benefit bone density, particularly in premenopausal and perimenopausal women.
Progesterone cream may also help women experiencing cyclical irregularity, especially leading up to menopause. Fluctuating hormone levels can lead to unpredictable or heavy periods. Using the cream on a cyclical schedule can provide a more organized hormonal rhythm. This application helps stabilize the uterine lining, which is useful for managing certain types of irregular bleeding.