RELATIONSHIP BETWEEN LIPOPROTEIN PROFILE IN CORD BLOOD WITH OBSTETRIC VARIABLES AND ANTHROPOMETRY IN NEWBORNS. DIFFERENCES RELATED WITH SEX

Introduction. Low birth weight has been recognized as a new risk factor for the development of cardiovascular disease in adulthood. Possible causes are insulin resistance of genetic origin or adaptation to poor fetal nutrition during intrauterine growth. The importance of lipid metabolism at birth is unknown and data on the relationship between birth weight and later lipid profile are contradictory. Patients and method. We performed a prospective study of a consecutive cohort of 265 full term newborns from single pregnancies. Data on maternal age, weeks of gestation, route of delivery; Apgar test, and anthropometric measures [head circumference, height, weight and ponderal. index (kg/m3)] were gathered. In addition, a cord blood sample was analyzed to determine concentrations of total cholesterol, low-density lipoprotein (LDL)- and high density lipoprotein (HDL)-cholesterol, triglycerides, and apolipoproteins A-1 and B. The possible relationship between lipid parameters and obstetric and anthropometric variables in newborns, as well as the influence of sex, were investigated. Results. Anthropometric measures were highly interrelated and were also correlated with gestational weeks, but no differences were found between the sexes, with the exception of head circumference. Girls showed a higher average concentration than boys of total cholesterol (68.7 vs. 62.2 mg/dl), HDL-cholesterol (23.4 vs. 21.2), LDL-cholesterol (37.3 vs. 32.9), apolipoprotein Al (70.7 vs. 66.5), and apolipoprotein B (30.8 vs. 28.4). Triglyceride levels were similar (40.1 vs. 40.7) between girls and boys. Significant and elevated correlations among lipid values were observed. However, there was only a weak correlation between gestational age and triglyceride values (rho,0.27) and between birth weight in girls and HDL (rho=0.26). No lipid differences were found between newborns with low or normal ponderal index. Conclusions. Lipid profile in newborns is more closely related to sex than to fetal growth. Any possible association of dyslipidemia with low birth weight would appear later in life.