Serum SP1, HPL levels and urinary estrogen/creatinine ratio in the detection of low birth weight.

Serum pregnancy specific beta 1 glycoprotein (SP1), human placental lactogen (HPL) and urinary estrogen/creatinine (E/C) ratio levels were determined to study their clinical significance in predicting low birth weight (LBW) in women with normal pregnancy and patients with LBW. The results showed that the sensitivity of urinary E/C ratio was better than that of serum SP1 and HPL, and was increased gradually with the reduction of fetal weight. The specificity in predicting LBW decreased gradually with the increase of serum SP1 and HPL levels and urinary E/C ratio. When serum SP1 level was less than 50 mg/L, HPL less than 2.0 mg/L, and E/C ratio less than 10, their specificity could increase over 90%. It is suggested that multi-indexes measurement would improve the accuracy for predicting LBW. We conclude that SP1, HPL and E/C ratio measurement could be an useful index for predicting LBW.