Lipid metabolism changes during pregnancy in order to support fetal growth and development .1,2,3 It is believed that this process is under hormonal control.4 There have been reports on serum lipid profile during pregnancy in Caucasians, but very little is known in Africans.5 There has not been a prospective cohort study using the same group of subjects throughout the course of pregnancy in women in this environment, hence this study. The study was therefore to determine serum triglyceride (TG), high density lipoprotein cholesterol (HDL), total cholesterol (TC) and low density lipoprotein cholesterol (LDL) in the three trimesters of pregnancy in the same women, in Benin City, Nigeria. Subjects were 50 pregnant women at the 6th week of pregnancy (first trimester) with no history of midwifery complications or systematic disorders. They were 25-34 yrs, (mean age 28±0.44 yrs). Controls were 50 non-pregnant women of the same age group that met the inclusion criteria. Demographic characteristics and midwifery information were collected by questionnaire. Written informed consent was obtained, and fasting venous blood samples were taken during the 1st, 2nd and 3rd trimesters. Blood pressure was recorded. Mean ± S.E.M. were calculated for all groups. lipid concentrations were measured enzymatically and expressed as mg/dl. Data was analyzed using ANOVA, and p< 0.05 was considered statistically significant. TG was lower in the control group than in the 1st, 2nd or 3rd trimester (138.44±0.6 vs 312.3±9.3, 252±3.1 and 247.4±2; p<0.05). However, among the pregnant women, TG concentration in the 1st trimester was higher than in the 2nd and 3rd trimester. The 2nd and 3rd trimester TG concentrations were not significantly different. HDL was significantly lower in the 1st trimester than in the control, 2nd or 3rd trimester (48.04±0.3 vs 58.34±0.4, 60.7±1.0, 56.3±0.5). LDL was highest in 1st trimester pregnancy and least in the control group (178.1±1.3 vs 83.04±1.2, 137.7±2.2 and 125.2±0.8; p<0.05 ). TC was higher in pregnant women than in the control (224.7±0.9, 216.8±0.9 and 231.7±2.2 vs 180.44±1.6; p<0.05). The significantly raised TG, TC and LDL in the pregnant women compared to the controls, especially during the 1st trimester provides evidence of natural rising in plasma lipids in normal pregnancy due to hormones.4 This rise in TG, TC, and LDL may be due to an increase in hepatic lipase activity and decrease in lipoprotein lipase active, the principle modulator of which is the pregnancy-induced hyperoestrogenaemia. It is concluded that the normal pattern of pregnancy- induced variations in serum lipids is observed in the women studied. The authors acknowledge all the women that took part in the study.