Lipid Metabolism in Gestational Diabetes

The purpose of this pilot study is to determine if, during pregnancy, women with GDM have an exaggerated lipid response compared to non-gestational diabetics. If a difference is noted, further studies will explore the possibility of screening gestational diabetics during their pregnancy for hyperlipidemia to determine if prenatal screening can predict postpartum risk for hyperlipidemia. In addition the relationship, if any between maternal lipid dysfunction and placental disease will be explored.

This will be a prospective cohort study. As part of routine prenatal care, women receive a one hour glucose challenge test to screen for gestational diabetes. Those women with elevated values then require a three hour glucose tolerance test, which is a diagnostic test for gestational diabetes. All women that are scheduled to receive a three hour GTT will be identified and ask to enroll in this study. 46 women whose three hour GTT is normal and thus do not have GDM, will be compared to 46 women with an abnormal three hour GTT and thus would have the diagnosis of GDM. Enrolled women will have a lipid panel consisting of; total cholesterol, triglycerides, HDL and LDL cholesterol at the time of their fasting glucose blood sample. In addition, a repeat lipid panel will be sent at the time of the third hour sample, to assess changes, if any due to the glucose challenge. Umbilical cord blood samples will be sent in order to obtain newborn lipid profiles. Women in both the GDM and normal groups will be asked to return 6-8 weeks

The purpose of this pilot study is to determine if, during pregnancy, women with GDM have an exaggerated lipid response compared to non-gestational diabetics. If a difference is noted, further studies will explore the possibility of screening gestational diabetics during their pregnancy for hyperlipidemia to determine if prenatal screening can predict postpartum risk for hyperlipidemia. In addition the relationship, if any between maternal lipid dysfunction and placental disease will be explored. Subsequent studies could also explore the possible perinatal complications associated with elevated lipids and or metabolic syndrome.

C. Experimental Design, Methodology and Expected Results

Study Design:

We propose a prospective cohort design.

Study Population:

All women that are scheduled to receive a three hour GTT to rule out gestational diabetes would be identified and ask to enroll in this study. Specifically, eligible patients will be women who failed their glucose challenge test (GCT) and are scheduled for the follow-up three hour glucose tolerance test (GTT). The GCT is routinely performed among all prenatal care patients at 24-28 wks gestation. The 3 hour GTT requires patients to be fasting overnight. A fasting blood glucose is sampled, and the patients are given a 100 gram glucose drink. Serum glucose samples are then taken at one, two and three hours after the glucose loading. The "exposed" group will be defined as women diagnosed with GDM (elevated glucose values on two or more samples in the three hour GTT). The "unexposed" group will be defined as women with no abnormal glucose values in the three hour GTT.

Eligibility Criteria:
Inclusion Criteria:

* Pregnancy
* Abnormal one hour glucose challenge test
* "Normal" controls group one hour test between 135 mg% and 150 mg%
* "Gestational diabetic" group with two abnormal values on a 3 hour GTT

Exclusion Criteria:

* History of diagnosis of diabetes, hypertension, heart disease or chronic renal disease
* Prior history of lipid disorder or metabolic syndrome
* Current medications thought to adversely influence glucose tolerance (i.e. prednisone or other steroids and systemic beta-mimetic drugs)
* Non-singleton pregnancy
* \< 16 years of age or over 40 years of age
* Not planning to deliver at Baystate Medical Center
* Twins