Reasons for Low Progesterone Levels

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Progesterone is a reproductive hormone produced naturally by the body. It is essential in regulating menstruation, fertility and pregnancy. Low progesterone levels may result in tender breasts, depression, hair loss, dry skin, insomnia, heavy periods, weight gain, vaginal dryness, thyroid dysfunction and infertility. Identifying the reasons for low progesterone is key to treating the condition.

High Estrogen

Estrogen and progesterone work to balance each other in the body. When estrogen levels increase for any reason, progesterone levels may drop. Because high estrogen levels suppress progesterone production, the problem becomes cyclical. Estrogen levels continue to rise, further lowering progesterone and triggering even higher levels of estrogen.

Lack of Exercise and Poor Nutrition

Regular exercise and a balanced diet are essential to progesterone production. Lack of activity can trigger hormone-producing glands in the body to become dormant and cease production of progesterone. A sedentary lifestyle and poor diet also increase the risk of obesity, which increases estrogen storage in the body, which drives down progesterone production.

Insulin Resistance

Insulin resistance occurs when the body is unable to effectively use the insulin it produces. Cells in the body are unable to take in progesterone when blood glucose levels are too high or too low. In addition, anything that causes spikes in insulin levels, such as eating refined carbohydrates and simple sugars, can result in a drop in progesterone levels. Insulin resistance may be caused by diabetes, obesity or polycystic ovarian syndrome.

Chronic Stress

Chronic stress reduces progesterone levels by increasing the production of cortisol, a stress hormone. Cortisol competes with progesterone for receptor sites in the cells. When cortisol levels remain high for prolonged periods, progesterone activity is impaired. In addition to reducing natural levels of progesterone, chronic stress may also interfere with progesterone therapy.


Certain medications can affect progesterone levels, including some steroids and hormonal therapies. Many oral contraceptives work by lowering progesterone levels to prevent ovulation and pregnancy. Other medications may interfere with the body's ability to absorb or use progesterone effectively. Only a doctor can determine if your medication is affecting your progesterone levels.

Polycystic Ovarian Syndrome

Polycystic ovarian syndrome, or PCOS, is both a cause and effect of low progesterone. In PCOS, the egg follicle migrates to a location other than the ovaries and fails to release an egg. This failure to ovulate prevents the natural surge of progesterone women experience during this point in the menstrual cycle. When the hypothalamus, a gland in the brain, detects the lack of progesterone it increases production of other hormones to stimulate the ovary. More estrogen is then produced, which further decreases progesterone levels.

Other Reasons

According to the American Association for Clinical Chemistry, low progesterone levels in late pregnancy may be caused by toxemia, and progesterone levels naturally decline during perimenopause. Sometimes doctors cannot determine the reasons for low progesterone.