Dietary protein in pregnancy: effect on anthropometric indices of the newborn infant

The effects of prenatal protein-energy malnutrition on ossification of fetal rat bones: a biochemical study

In fetal rats whose dams were fed a low-protein diet, 35S sulfate uptake into the growth plate of the long bone and rib was higher than in the control group. The elution pattern of guanidine-HCl extract in gel chromatography revealed that the malnourished group had more high molecular weight proteoglycans in the dissociative condition and a larger aggregated portion in the associative condition than did the control group; however, the same chondroitin-sulfate chain size existed. Calcium content did not differ in both groups. Aggregated proteoglycan or a high molecular weight proteoglycan that existed in the malnourished group probably played an inhibitory role in calcification. Prenatal protein-energy malnutrition may delay the change of proteoglycan character, which could affect mineralization of fetal bones.

Gestational protein-energy malnutrition affects the composition of developing skins of rat fetuses and their dams

1. Various biochemical variables of the skins of rat dams and their fetuses in which protein-energy malnutrition was induced during pregnancy were analysed. 2. One group of dams was fed on a 200 g protein/kg diet as a control and the other was fed on a 60 g protein/kg diet as an experimental group. Each group of dams was fed from day 13 of gestation until day 22. 3. Water, protein and hexosamine concentrations of the fetal skins in the malnourished group were greater than those in the control group, whereas in the dams' skins, protein concentration was greater in the malnourished group than in the control group. 4. Extractability of collagen with neutral salt and pepsin showed no difference between the groups in the skins of fetuses and dams. The content of type III collagen in the fetal skin did not differ between the groups, but was increased in the malnourished dams' skins compared with that of the control group. 5. The present study showed that protein-energy malnutrition during pregnancy significantly affects the metabolism of the skin in both fetuses and their dams. Furthermore, the skins of fetuses and dams are structurally altered in different ways by this nutritional stress.

Parental determinants of birth weight

As part of a study on causes of variation in birth weight, questionnaire data on parental measures were related to offspring birth weights recorded in the Medical Birth Registry of Norway. A genetic analysis of parent-offspring covariances in birth weight indicated that about 60% of the variance in birth weight could be explained by effects of fetal genes, while no effects of maternal genes were detectable. Multiple regression analysis showed that height and weight of both parents and maternal smoking status were associated with variation in birth weight. Socioeconomic status, educational attainment and paternal smoking habit had no independent effects. The adult, parental variables could only explain 10% of the variation in mean offspring birth weight.