Inclusion Criteria:

- Women 18-45 years old

- Premenopausal, defined as regular monthly menstrual cycles (every 25-35-days) for the
past 6 months and corroborated by a mid-luteal phase progesterone of > 3 ng/ml

- Willingness to use barrier methods of contraception during study and after completion
of study until menses resume

- Good general health with normal hemoglobin, prolactin, TSH, liver function tests
(SGOT, SGPT, bilirubin) and renal function tests (BUN, creatinine, alkaline
phosphatase)

Exclusion Criteria:

- Pregnancy, as determined by serum HCG at screening visit and immediately preceding
(day before or day of) GnRH agonist administration, or currently breastfeeding.

- Hot flushes, as determined subjectively (7-day hot flash diary) and objectively
(24-hour skin-conductance monitoring

- Mid-luteal phase progesterone <3ng/mL

- Clinically significant abnormalities in screening blood tests.

- BMI > 35 kg/m2

- Previously diagnosed osteoporosis or osteopenia

- Clinically significant depressive symptoms (Montgomery-Asberg Depression Rating Scale
(MADRS) score > 10)

- Psychiatric illness, as defined by clinical interview and the Mini-International
Neuropsychiatric Interview (MINI).

- Sleep apnea or periodic limb movement of sleep (PLMS) either diagnosed previously or
on a screening polysomnography (PSG) study.

- Contraindication, hypersensitivity, or previous allergic reaction to GnRH agonists

- Current or recent (one month) use of centrally active medications (antidepressants,
anxiolytics, hypnotics, or the anticonvulsant gabapentin.

- Current or recent (3 months) use of systemic hormone medications

- Night shift workers

- Current or recent (one month) over-the-counter (OTC) medications that may affect hot
flashes, sleep, or mood (eg diphenhydramine, St. John's Wort, Black Cohosh, and other
phytoestrogen supplements)

- Abnormal vaginal bleeding

- History of any medical diseases that may put subject at risk when treated with study
medication. These include a history of thrombo-embolism or cardiovascular disease,
congestive heart failure or other conditions requiring sodium restriction, spinal
cord compression, metastatic vertebral lesions, memory disorders, urinary tract
obstruction or history of liver, kidney, pulmonary, or metabolic disease that may put
subject at risk when treated with study medication.