Reference interval for 24-hour urinary protein excretion in uncomplicated women with twin pregnancies

Physiological proteinuria levels were approximately doubled in late pregnancy in women with twin pregnancies compared to early pregnancy, and the upper limit of normal 24-h UTP excretion is 415.7 mg in late pregnancy. Moreover, the threshold for elevated proteinuria in twin pregnancies could be higher than in singletons from the second trimester onwards. Understanding these changes is essential for precise twin management and patient counseling.