Objective  To explore the high risk factors of intrauterine fetal death of singleton pregnancy.

  Methods  Clinical data of 79 singleton pregnancies with stillbirth delivered in Affiliated Hospital of Yangzhou University were analyzed retrospectively. The general situations (age, pregnancy and delivery times, gestational age, fetal movement, etc.), complications or comorbidity of pregnant women, placenta situation, umbilical cord situation, fetal situation and amniotic fluid volume were observed.

  Results  Except for unknown reasons (22/79, 27.9%), the high risk factors of stillbirth were umbilical cord factor (26/79, 32.9%), maternal factor (13/79, 16.5%), fetal abnormality (8/79, 10.1%), abnormal amniotic fluid volume (8/79, 10.1%), placenta factor (2/79, 2.5%). Stillbirth mainly occurred in late pregnancy caused by umbilical cord, and in the second trimester by fetal abnormalities and abnormal amniotic fluid volume, and the difference was statistically significant (P < 0.05). The proportion of stillbirths caused by maternal comorbidity or complications in the older pregnancy (aged ≥ 35 years) was higher than that in the age-appropriate group (aged 20 to 35 years), and the difference was statistically significant (P < 0.05).

  Conclusion  It is possible to reduce the incidence of stillbirth by the measures of strengthening the management of high-risk pregnant women, actively dealing with pregnancy complications and comorbidity, identifying the high-risk factors of stillbirth early and intervening, improving the diagnostic rate of excessive helix of umbilical cord and emphasizing the importance of fetal movement counting.