The purpose of the study is to prospectively evaluate a noninvasive, near-infrared based method for measuring glucose concentration relative to invasive blood reference measurements. The initial phase of the study will be focused on procurement of the data needed to develop a robust, accurate calibration. The second phase will be focused on performance evaluation of the system.

Currently, individuals with diabetes must use an invasive finger stick methodology for the determination of their blood glucose levels. Although current technology glucose meters use a smaller amount of blood than older generation meters, the pain and inconvenience associated with this invasive measurement is the number one reason cited for inadequate or infrequent blood glucose monitoring. In fact up to 67% of patients with diabetes fail to routinely monitor their blood glucose levels. A survey of 1895 patients showed that finger soreness was the most common reason given for self-reported noncompliance with testing recommendations, followed by pain, inconvenience, fear of needles, and "other" (including cost), (Diabetes Care August 2001 vol. 24 no. 8 1502-1503). The ability to make a painless blood glucose measurement using only light would address the pain and inconvenience issues associated with current technology glucose meters.

The initial application of the technology is associated with the monitoring of Gestational Diabetes. The International Association of Diabetes and Pregnancy Study Groups (IADPSG) recently released recommendations for diagnosing gestational diabetes, as well as clarifying the benefits of treatment (Diabetes Care, 2010;33:676-682). The IADPSG cited research that found significant graded relationships between increasing maternal glucose levels and the frequency of four primary and five secondary outcomes. For example, with a 1-standard deviation increase in maternal fasting, 1-hour, and 2-hour plasma glucose levels, there was a corresponding 38%, 46%, and 38% increased risk, respectively, in the primary outcome of birth weight >90th percentile, and a 5%, 18%, and 16% increased risk, respectively, of the secondary outcome of premature delivery before 37 weeks gestation (N Engl J Med 2008;358:1991-2002).

Inclusion Criteria:

• Female at least 20 years of age but not older than 50 years of age
• Female with Type I or Gestational diabetes based on ADA criteria
• Female with Type II diabetes and A1c of greater than 7.0 as measured on a Bayer A1C Now meter
• May include female healthy volunteers.

Exclusion Criteria:

• Subject requires hemo-dialysis
• Severe heart disease as evidenced by peripheral edema
• Liver disease as evidenced by jaundice
• Active alcohol or drug abuse
• Body Mass Index (BMI) > 35 kg/m2
• Hand size too large to fit in the optical measurement instrumentation
• Middle finger width of less than 5 mm
• Skin damage at optical sampling site on hand
• Currently taking prednisone or other systemic steroids
• Tattoo at the optical sampling site

The Human Subject population consists of female subjects between the ages of 20 and 50. Subjects must have been diagnosed with either Type I, Type II, or Gestational diabetes and may utilize healthy individuals for the validation phase. Up to 100 subjects may be recruited to participate in this study. Subjects will be recruited from the community and will be selected to ensure a representative sample of the projected intended use population. Efforts will also be made to ensure a broad and even distribution of ages (between 20 and 50 years old) and ethnicities.