Objective To investigate the change of umbilical cord blood gas from early-stage neonates with pregnancy-induced hypertension syndrome (PHIS) affected mothers and its influence upon internal environment of body,and to evaluate the significance of postpartum umbilical cord blood gas analysis.Methods Retrospective study of 101 neonates(born of 97 PHIS-affected mothers),41 cases of mild group,34 cases of moderate group,26 cases of severe group,and enrolled 52 neonates born of non-PHIS mothers as the control group.Prior to neonate's first breath,umbilical cord artery blood gas analysis was performedimmediately to determine the values of pH,arterial carbon dioxide partial pressure (PaCO2),arterial oxygen tension (PaO2),HCO3-,base excess (BE),and Apgar score was completed within 1 min after birth.Results The pH,PaO2,HCO3-,BE in severe group was significantly lower than those in mild group,moderate group,and control group [7.16 ± 0.18 vs.7.25 ± 0.09,7.22 ± 0.11,7.29 ± 0.08 ; (12.01 ± 2.75) mmHg (1 mmHg =0.133 kPa) vs.(18.35 ± 1.75),(14.21 ± 2.01),(22.23 ± 1.45) mmHg; (17.11 ± 2.42) mmoFL vs.(19.82 ±3.85),(17.32 ± 3.21),(22.56 ± 3.38) mmol/L; (-9.15 ± 0.32) mmol/L vs.(-7.95 ± 0.60),(-7.21 ± 0.08),(-6.76 ± 0.03) mmol/L] (P ＜ 0.05),the PaCO2 in severe group was significantly higher than that in mild group,moderate group,and control group [(61.84 ± 32.93) mmHg vs.(54.48 ± 12.82),(58.38 ± 15.32),(51.66 ± 10.52) mmHg] (P ＜ 0.05),Apgar score 1 min after birth was positively correlated with umbilical arterial pH (P ＜ 0.05),the lower Apgar score,the lower pH.Among 65 cases of Apgar score ≤ 7 scores,37 cases of acidosis (pH ＜ 7.20),the incidence rate was 56.92％ (37/65) ; among 88 cases of Apgar score ≥ 8 scores,11 cases of acidosis,the incidence rate was 12.50％ (11/88),the difference was statistically significant (P ＜ 0.01).Conclusions Umbilical cord blood gas analysis is more objective than Apgar score,which could reflect neonate's hypoxia-ischemia degree bore of PIHS mothers,as well as contributed to the assessment of neonate' s prognosis.Conventional umbilical cord blood gas analysis is necessary for neonates bore of PIHS-affected mothers.Enhanced monitoring should be performed in a timely manner on those neonates born after intrauterine distress signs or with low Apgar score,the prevention and therapy as early as possible can improve the quality of birth.