PIP: 45 women aged 27-37 participated in a 6-month study of the effects of 3 kinds of oral contraceptives (OC), (DSG, LNG, and NET) on changes in lipoprotein and apolipoprotein metabolism. The women took each of the 3 kinds of OC for 3 cycles sequentially and had blood tests after taking each kind of OC. The results of the blood tests showed that DSG was associated with an increased level of HDL-C, TG, TC, apo AI, and apo AII; and reduced the ratio of LDL-C/HDL-C. Compared with DSG, LNG was associated with a reduction in HDL-C level, the changes in other parameters were smaller than DSG. The comparison of LNG and NET was similar to that of DSG and LNG. Comparing NET with DSG, the increase of HDL-C and apo AI induced by NET was not as high as that of DSG; nevertheless, the changes in other parameters induced by DSG and NET were similar. The LDL-C/HDL-C ratio and apo AI/apo B ratio induced by DSG were the most favorable. Using DSG or NET can result in an increase of serum protein levels. LNG reduced the HDL-C level, but its changes in other serum protein levels were not significant. An increase in the HDL-C level is protective of the cardio vascular system and is beneficial to women who have a low level of HDL-C. Alternating the use of different kinds of OCs could reduce the side effects of changing serum lipoprotein metabolism. As the subjects of the study were healthy young women, the association of OCs with the risk of cardiovascular disease (CVD) other studies could not be proved, but the possibility of higher risk of CVD in OC users may be present in view of the increased TC/HDL-C and LDL-C/HDL-C ratios in OC users.