Vitamin D is present in food either naturally or by fortification and included in nutritional supplements. It is also synthesized photochemically by the skin from ultraviolet B radiation. Vitamin D synthesis varies by season and with latitude as well as according to intensity of skin pigmentation. Recent research in the United States found lower circulating levels of 25 (OH) D, the primary indicator of vitamin D status, among minority women who were either pregnant or in their reproductive years. The extent to which maternal vitamin D has an influence on the course and outcome of human pregnancy remains to be more completely studied. We propose to use the HPLC method to assay cholecaliferol (vitamin D3) and ergocalciferol (vitamin D2) to assess maternal vitamin D status. This will be accomplished by analyzing existing fasting samples and data derived from the 2001-2006 cohort (N=1141) of young, low income minority gravidae from Camden, New Jersey to determine:
- The prognostic importance of maternal vitamin D status for birth weight, gestation duration and poor pregnancy outcomes (low birth weight, preterm delivery, fetal growth restriction).
- The relation of maternal vitamin D status to important complications of pregnancy (gestational diabetes and pre-eclampsia).
- The relationship of maternal vitamin D status to maternal diet and supplement use, season of year, ethnicity, overweight/obesity, and other maternal characteristics.
Primary Outcome Measures:
- Maternal Vitamin D Status [ Time Frame: Up to 5 years ]
Our primary objective is to determine the prognostic importance of maternal vitamin D status for birth weight, gestation duration and poor pregnancy outcomes (low birth weight, preterm delivery, and fetal growth restriction).
Secondary Outcome Measures:
Biospecimen Retention: Samples With DNA
Other Outcome Measures:
- Relationship of Vitamin D to maternal diet, etc. [ Time Frame: Up to 5 years ]
To describe the relationship of maternal vitamin D status to maternal diet and supplement use, season of year, ethnicity, overweight/obesity, and other maternal characteristics.
Blood and urine collection: Fasting (>8 h) maternal blood samples were collected at entry to care and week 28 of gestation. Blood specimens were also collected at 1-hour of the 50g glucose challenge test. Fasting blood samples collected at each visit were immediately refrigerated and centrifuged at 4oC. Plasma and serum were preserved from each patient (at -70oC) until assayed. 20 ml of urine was collected at entry to care and week 28 in metal free plastic containers and stored at -70oC.
| Study Start Date:
| Primary Completion Date:
||September 2007 (Final data collection date for primary outcome measure)
Study data pulled from already collected data (N=1141 from the Camden Study of low income gravidae and minority gravidae (White, African-American and Hispanic) living in the northeastern United States (New Jersey).