What are considered dangerously high levels of protein in urine during a 24 hour collection during pregnancy?

Pregnant proteinuria. Preeclampsia (p) is a syndrome affecting multiple organs and diagnosed by presence of high blood pressure along with loss of protein in urine (> 300 mg per day). If the woman has this level after 20 weeks of pregnancy, it could be a sign of p developing. If this level is found before 20 weeks, it may be due from a pre-existing condition.