Inclusion Criteria:

1. Patients must have a measured BMI greater than or equal to 30 kg/m2 (obese) or less
than or equal to 25 kg/m2 (lean) at the time of enrollment.

2. Patients must be between the ages of 30 and 55 years old at the time of enrollment.

3. Patients must not have taken any birth control (including pills, patch, injectables)
for at least three months prior to enrollment.

4. Patients may not be pregnant at the time of enrollment (defined by negative urine
pregnancy test).

5. Patients must have signed an informed consent indicating they are aware of the
investigational nature of this study.

6. Patients with a history of non-metastatic cancer may be included if they have not
undergone cancer treatment for at least six months prior to enrollment.

Exclusion Criteria:

1. Patients who have had a prior hysterectomy.

2. Patients who are pregnant or have a positive pregnancy test.

3. Patients with a prior history of endometrial hyperplasia or endometrial cancer.

4. Patients who are currently on birth control (including pills, patch, or injectable
birth control).

5. Patients who are postmenopausal (have not had a menstrual cycle in greater than or
equal to one year).

6. Patients who have ever been on selective estrogen receptor modulators (SERMs) in the
past including Tamoxifen and Raloxifene.

7. Patients with a history of metastatic cancer (any type).

8. Patients with a history of non-metastatic cancer who are currently undergoing therapy
for that cancer or who have received therapy within six months of enrollment.

9. Patients with a history of non-metastatic cancer who have received any type of
hormonal therapy including but not limited to aromatase inhibitors, GNRH-agonists,
and Zoladex.

10. Patients who have had prior radiation to the pelvis.

11. Patients with psychiatric disorders that would interfere with consent.