Objective: To review the relationships between various laboratory measures relating to nutrition and pregnancy outcome. The data were obtained during the investigation entitled "Successive small-for-gestational-age births study".
Methods: A total of 289 pregnant women of the 1545 who participated in the study between 1986 and 1988 in Birmingham, Alabama, USA. The following determinations were done using the serum samples obtained at 18 and 30 weeks of gestation: zinc, folate, vitamins A and E, and proteins (alpha-2-macroglobulin, retinol-binding protein, prealbumin, and albumin). These laboratory values were correlated with various measures of pregnancy outcome including the incidence of fetal-growth retardation and maternal infections during the perinatal period and birth weight and Apgar score of infants.
Results: Serum folate concentrations showed positive relationships with the incidence of fetal-growth retardation as well as birth weight of infants, and alpha-2-macroglobulin was negatively correlated with birth weight. These relationships were significant after adjusting for factors previously known to affect the birth weight of infants. The concentrations of serum zinc, vitamins A and E, and proteins did not show significant correlation with measures of pregnancy outcome.
Conclusion: Among the laboratory measures evaluated in this study, serum folate and alpha-2-macroglobulin concentrations correlated with pregnancy outcome. Further research is warranted to investigate the mechanism(s) of the relationship between serum alpha-2-macroglobulin and birth weight of infants.