Table 1.

Characteristics of the subgroups of preeclampsia.

PE Subgroup	Comment
Early onset PE(<34 weeks of gestation)	Consist of about 10% of total cases of PE.Placental dysfunction is more likely to occur; increase IUGR, maternal and perinatal mortalities.Renal function indicators (Cr, BUN and uric acid) were significantly higher, but alkaline phosphatase levels are lower, in early onset PE.
Late onset PE( ≥34 weeks of gestation/during labor)	Majority of cases of PE.Normal or big for gestational age fetus at delivery at term

BUN: blood urea nitrogen; Cr: serum creatinine; IUGR: intrauterine growth retardation; PE: preeclampsia.