The normal menstrual cycle is produced by a series of hormonal signals that starts with the release of gonadotropin-releasing hormone (GnRH) from the hypothalamus. The hypothalamus is located in the brain and is often referred to as the master gland. GnRH then acts on the pituitary gland and causes it to release two hormones, follicle stimulating hormone (FSH) and lutenizng hormone (LH). LH and FSH act on the ovary and cause it to release the hormones directly involved in menstruation, estrogen and progesterone.

The purpose of this research study is to evaluate the hypothalamic-pituitary-gonadal axis activity as measured by pituitary hormones, FSH and LH in response to intravenous doses of gonadotropin releasing hormone (GnRH) in menstrual cycle-related hormones.

This protocol is designed to accompany clinical protocol #81-M-0126, "The Phenomenology and Biophysiology of Menstrually Regulated Mood and Behavior Disorders", as well as the submitted protocol, "The Phenomenology and Biophysiology of Climacteric and Menopause-Related Mood and Behavioral Disorders." Its purpose will be to evaluate hypothalamic-pituitary-gonadal axis regulation as measured by pituitary gonadotropin, i.e., follicle stimulating hormone (FSH) and luteinizing hormone (LH), response to intravenous administration of gonadotropin releasing hormone (GnRH) in menstrual cycle-related mood disorders.

Age 18-65.

Female.

Use of barrier methods of birth control.

Not pregnant.

Not taking ongoing medications.

No medical illnesses.