Biochemical findings on blood samples from 102 pregnant women in four age groups, 12-17, 18-19, 20-24, and 25-32, are reported. Samples represent 8 antepartum periods of 4 weeks each and 3 postpartum periods over 6 weeks. Blood analyses were carried out for hemoglobin, plasma iron, plasma total protein, glucose, plasma alkaline phosphatase, plasma ascorbic acid, plasma vitamin A and carotene, erythrocyte transketolase as a measure of thiamine status, plasma cholesterol, plasma lipid phosphorus, plasma total fatty acids, and triglyceride fatty acids. For the most part, means of these nutrients were in acceptable ranges for all age groups. Although adolescents had better levels than anticipated, the two younger groups on several occasions had means significantly lower than those of the two older groups, indicating that they needed greater nutritional support during pregnancy than older women.