Background: Pregnancy consists of a series of small, continuous physiologic adjustments that affect the metabolism of all nutrients. An important external risk factor for pregnant women and newborn health is unbalanced nutrition of pregnant women. Study Setting: This comparative study was conducted in the department of Biochemistry Liaquat University of Medical and Health Sciences Jamshoro with collaboration of Gynecological and Obstetrics department of Liaquat University Hospital, Jamshoro/Hyderabad and Muhammad Medical College. Study Design: Case control and comparative study Duration of study: One year from August 2008 to July 2009. Sample size: 120 cases Inclusion criteria: Women who were confirmed Primigravida (1st Pregnancy) with age ranged 20 to 35 years. Non pregnant women (control group) with age ranged 20 to 35 years. Exclusion criteria: Pregnant women having any history of hypertension, renal disease, diabetes or any other complication like toxemia of pregnancy were excluded from the study. Results: Total 120 women were selected in this study, 90(75.0%, n = 120) were pregnant and 30 (25.0%, n = 30) were non pregnant. 112 (93.3%) woman had regular diet, the Mean + SD of serum albumin was 4.405 + 0.57 and 08 (6.66%) women were non vegetarian the Mean + SD of serum albumin was 4.212 + 0.35. No significant difference was noted. (P value 0.38).Of these 90 pregnant women, there were 26(28.88%) women in First Trimester with Mean + SD gestational weeks 9.0 + 1.87, 20(22.22%) women were seen in second trimester with Mean + SD gestational week 20.3 + 3.68 and 44(48.88%) women were found in third trimester with Mean + SD gestational weeks 31.5 + 2.74. There was highly significant difference among the means of these trimesters (P value < 0.001) Conclusion: The evidence that during pregnancy level of albumin is decreased in comparison to control group. This change in level of serum albumin is dependent on various factors as period of gestation, dietary habits, education, socio-economic status and age.