Preeclampsia is a pregnancy complication; early identification with increased risk is one of the key goals in obstetrics. In a nested case control study, serum uric acid and calcium measured in first and second trimesters of pregnancy were correlated with Xanthine oxidase (XO) activity, mean arterial pressure (MAP) and fetal birth weight. The mean ± SD of uric acid (2.01 ± 0.85, 4.8 ± 1.93), calcium (10.88 ± 1.97, 9.72 ± 2.04), MAP (84.32 ± 6.71, 78.40 ± 8.53) and XO activity (11.96 ± 1.91, 14.05 ± 3.09) of the study group (n=86) were observed in the first and second trimesters respectively. First trimester normotensive group (n=79) and preeclampsia cases (n = 7), showed a mean ± SD of uric acid (1.93 ± 0.80, 2.9 ± 0.88), Calcium (10.92 ± 1.9, 10.6 ± 1.72), MAP (84.19 ± 6.75, 85.71 ± 6.58) XO activity (11.82 ± 1.83, 13.57 ± 2.21). In the second trimester, normotensive group and preeclampsia cases showed a mean ± SD uric acid (4.6 ± 1.75, 7.3 ± 2.19), Calcium (9.4 ± 1.85, 12.9 ± 1.04), MAP (76.41 ± 5.41, 100.95 ± 2.52) and XO activity (13.37 ± 1.93, 21.70 ± 3.50). Statistical analysis revealed a non-significant positive correlation in first trimester between uric acid and MAP (r = +0.116, p = 0.288), negative correlations between uric acid and fetal birth weight (r = −0.118, 0.279) and between calcium and MAP (r = −0.288, p = 0.007). In the second trimester, significant positive correlations were observed between uric acid (r = +0.246, p = 0.022), calcium (r = +0.326, p = 0.007) with MAP along with a significant negative correlation between uric acid (r = −0.641, p = 0.000), calcium (r = −0.316, p = 0.003), Proteinuria (r = −0.514, p = 0.000) with fetal birth weight. The screening of first and second trimesters XO activity, uric acid, calcium and MAP during pregnancy is beneficial in identifying women likely to develop