The role of prostaglandin E2 (PGE2) and prostaglandin F2alpha (PGF2alpha) in the pathogenesis of hypertension and altered renal functions, which are the main symptoms of preeclampsia, has gained importance. Serum and urine samples of 59 women (24 preeclamptic pregnant (PEP), 20 normotensive pregnant (NTP) and 15 nonpregnant) were investigated by means of prostaglandin levels and urea, creatinine and creatinine clearance values. PEP patients, when compared with NTP patients, show a significant decrease in PGE2 and PGF2alpha levels (p < 0.01 and p < 0.05, respectively) accompanied by changes in some parameters of renal function such as serum urea, creatinine and creatinine clearance. Although disorders in prostaglandin levels may be responsible for some renal pathologic changes, renal functional and morphologic alterations may also result in abnormal prostaglandin activity.