Materials and Methods: A total of 600 patients who referred to Milad hospital in 2011 participated in this study. Second and third trimester hemoglobin levels were measured. The association between the level of maternal hemoglobin and the incidence rate of preeclampsia and gestational diabetes was evaluated. In addition, the association between the second and third trimester hemoglobin level and education, job, history of abortion, as well as the use of calcium, folic acid, iron, and multivitamin pills was evaluated.

Results: The results indicated that the second and third trimester maternal hemoglobin levels were high in patients with gestational diabetes and preeclampsia. Further, the relative risk of GDM was 2.12 times higher in the high hemoglobin group during the second trimester of pregnancy compared to the normal hemoglobin group (CI = 1.14-3.94) and it was 1.47 times higher in the third trimester (CI = 0.78-2.7). Furthermore, the relative risk for preeclampsia in the high hemoglobin group was 2.33 times more than normal one (CI = 1.16-4.66) and in the third trimester, it was 1.33 higher (CI = 0.66-2.66).

Conclusions: The high hemoglobin, especially in the second trimester is associated with a higher risk of subsequent preeclampsia and GDM. Hence, women with high hemoglobin in their second trimester are at greater risk of developing GDM and preeclampsia. Therefore, early detection and prevention reduce undesirable effects.