Objective:To determine whether maternal β-human chorionic gonadotropin（β-hCG） level in second-trimester may be associated with subsequent development of pregnancy-induced hypertension（PIH）.Methods:Seven hundred and sixty-two women in mid-trimester were to have maternal urine β-hCG standardized concentrations and maternal serum β-hCG measurements.Their case histories were recorded and reviewed from mid-trimester to delivery.The relation was observed between maternal urine

serum markers and subsequent development of PIH.Results:Among 762 women

504 cases were normal pregnancies

42 cases had PIH

94 cases had premature rupture of membrane （PROM）

69 cases had preterm delivery （PD）

53 other cases were excluded by various reasons.The levels of maternal urine

serum β-hCG in PIH were （61.75±9.78） IU/L and （304.56±54.17） ng/mg respectively

which were higher significantly than normal pregnancy group （[20.65±7.61] IU/L and [146.34±47.81] ng/mg

P<0.05）.When maternal serum

urine β-hCG levels ≥2 MOM（multiple of mean）

the incidences of developing PIH were increased significantly as compared with those of β-hCG <2 MOM women.The incidence of PIH increased from 5.1% in pregnancies with urine β-hCG ≥2 MOM to 11.7% in cases with urine β-hCG ≥4 MOM.Conclusion:The elevation of maternal mid-trimester urine

serum β-hCG levels is not only an early signal for dysfunction of placenta but also a dangerous signal for development of PIH.Second-trimester maternal urine β-hCG measurement proves to be superior to serum marker in clinical prediction.