Arlyn G. Riskind     
Director, Media Relations    
Phone: (301) 941-0240     
Email: ariskind@endo-society.org

Aaron Lohr
Manager, Media Relations
Phone: (240) 482-1380
Email: alohr@endo-society.org

 

A moderate dose of the female hormone progesterone shows promise in improving sleep quality and reducing nighttime awakenings in postmenopausal women, a preliminary study finds. The results will be presented Sunday in San Diego at The Endocrine Society’s 92nd Annual Meeting.

“Progesterone has no effect on undisturbed sleep but may restore normal sleep when sleep is disturbed,” said the author who presented the results, Anne Caufriez, MD, PhD, an associate professor at the Université Libre de Bruxelles, Brussels, Belgium.

Although the study was small and further research is needed, Caufriez said bioidentical progesterone or a specifically designed synthetic form “may one day become a treatment of choice in several forms of sleep disturbances, in particular in postmenopausal women.”
 
Commonly prescribed sleep medications contain a benzodiazepine or a benzodiazepine derivative, which increase sleep duration but may inhibit deep sleep and thus deteriorate sleep quality, she said. In addition, these medications may have side effects such as dizziness and mental confusion, and their chronic use rapidly results in addiction.

Progesterone, on the other hand, is a hormone that females naturally produce until menopause, when the body produces only minimal amounts. Caufriez said, “This sharp decrease in progesterone secretion after menopause may indeed contribute to insomnia,” which by some estimates occurs twice as often after menopause.

Caufriez and her co-workers performed sleep studies on eight healthy postmenopausal women, ranging in age from 48 to 74 years. Women underwent two series of sleep studies: once after receiving three weeks of treatment with progesterone capsules (300 milligrams daily) and once after receiving placebo (“dummy”) capsules for three weeks. Neither the women nor the sleep study team or investigators knew which test drug was given. On each occasion, sleep studies took place on two consecutive nights. During the second night, sleep was disrupted by an intravenous catheter and blood sampling used to determine hormone levels.

On the first night without the catheter in place, sleep was normal and similar whether women had been receiving placebo or progesterone treatment. During the second night, women had markedly disturbed sleep after receiving placebo but not when they had received progesterone. With progesterone use, the total duration of awakenings was 50 percent lower than with placebo. The brain activity of slow-wave, or deep, sleep increased by 44 percent compared with placebo, showing better sleep quality, according to the abstract.

At a dose of 300 milligrams a day, natural progesterone has no side effects in postmenopausal women, according to Caufriez. On the contrary, progestins, synthetic derivatives of progesterone found in birth control pills, and also frequently used in hormone replacement therapy after menopause, act on different brain receptors than progesterone does and may cause insomnia.

The Belgian research fund Fonds de la Recherche Scientifique Médicale and the European Union supported this study.

 

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Founded in 1916, The Endocrine Society is the world's oldest, largest, and most active organization devoted to research on hormones and the clinical practice of endocrinology. Today, The Endocrine Society's membership consists of over 14,000 scientists, physicians, educators, nurses and students in more than 80 countries. Together, these members represent all basic, applied, and clinical interests in endocrinology. The Endocrine Society is based in Chevy Chase, Md. To learn more about the Society, and the field of endocrinology, visit our web site at www.endo-society.org.