Many important changes may occur during pregnancy on various organ systems of the body including kidneys. Pregnancy period has significant effects on renal structure and function. The urinary system showed significant physiological and structural changes during pregnancy.
 In the present study, a total of 140 blood samples of pregnant women were collected from Al-Zahrra hospital, Iraq- during a period of July 2014 to February 2015.Pregnant women were divided according to their gestational period into three groups, first, second and third trimester group. Kidney functions including globulin, blood urea, serum creatinine and albumin were measured in blood of these pregnant women.
The results showed highly significant increase in the level of albumin, creatinine and blood urea in first trimester as compared with control group(pregnant women with normal kidney function test) .The results showed highly significant increase in the levels of globulin and protein in second trimester and gradually decline in the third trimester as compared with control group.
In conclusion, many significant physiological changes may occur in kidney functions during pregnancy trimesters.