Fifteen cases of primiparas and their offsprings (fetal cord) were investigated with regard their serum total, free and esterified cholesterol by means of Liberman Buchard reaction. The serum ${alpha}-and;{eta}-lipoprotein$ were analyzed by cellulose acetate electrophoresis, and the serum atherolipid numbers were calculated on the bases of the serum total cholesterol and ${eta}-/{alpha}-$ lipoprotein ratio, with the following conclusion. 1.Total, free and esterified cholesterol are $178.9{pm}25.3$, $45.1{pm}12.6$ and $133.7{pm}20.6;mg.%$ in the normal control women, $201.5{pm}29.5,;58.7{pm}42.1$ and $157.1{pm}26.2;mg.%$ in the maternal blood, showing hypercholesterolemia in the latter as compared to the former. 2. The serum total, free and esterified cholesterol in the cord blood are $94.5{pm}20.4$, $32.9{pm}1.5$ and $61.2{pm}18.9mg.%$, showing hypocholesterolemia as compared to the control women and maternal blood. 3. The serum ${alpha}-$, $pre-{eta}$, ${eta}-lipoprotein$ and chylomicron are $24.2{pm}4.2$, $17.3{pm}3.4$, $51.8{pm}4.8$ and $6.0{pm}1.6%$ in the normal women, whereas $14.9{pm}2.1$, $22.2{pm}5.1$, $58.7{pm}3.3 and 3.1{pm}1.2%$ in the maternal serum, $32.4{pm}8.1$, $28.8{pm}2.4$, $25.8{pm}7.0$ and $3.1{pm}0.9%$ in the cord serum, showing $hyper-{eta}-lipoproteinemia$ in the former and $hypo-{eta}-lipoproteinemia$ in the latter. 4. The serum atherolipid number of the normal control women, maternal cord blood are $4.21{pm}1.24$, $8.02{pm}1.42$ and $1.12{pm}0.37$, showing hyperlipemia in the former and hypolipemia in latter. 5. The relative ratio of the serum free and esterified cholestrol of both normal control women and maternal blood is about 1 : 3, while that of the fetal blood about 1 : 2. 6. The relative ratioes of the serum ${alpha}-and$ ${eta}-lipoprotein$ in the control women is about 1 : 2, that of materna blood about 1 : 3 and that of the fetal blood about equal magnitude. 7. The serum esterified cholesterol, ${alpha}-lipoprotein,;{eta}-/{alpha}-lipoprotein$ ratio and atherolipid number fluctuates are proportionally between the maternal and fetal blood, while the serum free, total cholesterol and ${eta}-lipoprotein$ between the two vary inversely with statistically significant corelations. 8. It is apparent from the above results that the fetal nutritional demand for lipids resulted from hypocholesterolemia and hypo ${eta}-lipoproteinemia$ seems to be met satisfactorily by maternal hypercholesterolemia and hyper ${eta}-lipoproteinemia$, which seems to pose a significant maternal-infant nutritional relationship. A brief ciscussion was made on these conciusion in the light of biochemistry and endocrinology.