Clinical Trial: Effect of Bright Light on Sex Hormones and Ovulation in Humans

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title:

Brief Summary: The study investigated whether bright artificial light may influence menstrual cycle and ovulation conclusively, and what underlying hormonal changes for this effect are.

Detailed Summary: Several studies have shown a shortening of the menstrual cycle following light therapy in women with abnormally long menstrual cycles or with winter depression, which suggests that bright light may influence sex hormones and ovulation. The study was designed to investigate this possibility. Twenty-two women with slightly lengthened menstrual cycles and without clinically evident endocrine abnormalities completed a study lasting for two menstrual cycles separated by an off-protocol episode of at least 1 menstrual cycle. Bright light therapy was administered for a week at home during one experimental cycle, and dim light during another cycle (placebo-controlled, crossover, counter-balanced order). Daytime blood sampling and ultrasound scan were performed before and after a week of light therapy, on the ~7th and 14th days after menstruation onset. Ultrasound examination was repeated further to document ovulation. Serum was assayed for thyroid-stimulating hormone, prolactin, luteinizing hormone, follicle-stimulating hormone, and estradiol. The preliminary results were reported at the SLTBR meeting in June, 2005.
Sponsor: Russian Academy of Medical Sciences

Current Primary Outcome:

Original Primary Outcome:

Current Secondary Outcome:

Original Secondary Outcome:

Information By: Russian Academy of Medical Sciences

Dates:
Date Received: May 17, 2006
Date Started: September 2003
Date Completion:
Last Updated: October 18, 2009
Last Verified: October 2009