Comparison of the high risk factors of single and twin premature birth with the outcome of premature infants

LI Si-hui; GONG Jing-jin; MO Jin-hua; LIU Gui-hong; YU Bo-lan; LIU Shi-liang; WANG Hai-bin; CHEN Dun-Jin

doi:10.19538/j.fk2018020112

Abstract：Objective To investigate the characteristics of high risk factors of twin preterm birth and singleton premature birth as well as the outcomes of single and twin premature infants.Methods A retrospective analysis was conducted on clinical data of single and twin pregnant women and newborns from January 2009 to December 2015 in the Third Affiliated Hospital of Guangzhou Medical University.Results There were 36931 newborns,including 2080 twins and 34851 singleton pregnancies during the study period,of which 5877 were premature births:1395 were twin premature (twin premature birth group)and 4482 were singletons (single premature birth group);premature birth rate was 15.91％;twin premature birth rate was 67.07％,and singleton premature birth rate was 12.86％,twin premature birth rate being significantly higher than singleton rate;the difference was statistically significant (P ＜ 0.05).Preterm birth rates of twin pregnant women were higher in the age group of under 22 years old,22 to 26 years old,26 to 30 years old,30 to 34 years old,34 to 39 years old and over 39 years old than those of single fetus (the premature birth rate of singletons and twins were 19.65％ vs.64.86％,11.45％ vs.70.85％,10.49％ vs.68.16％,12.88％ vs.65.41％,19.67％ vs.64.51％ and 22.83％ vs.68.42％,P＜0.05).Comparing the birth rate at different gestational weeks,the rate of twin group was higher than that in single group between 20 and 37 weeks.The risk factors of preterm birth were compared and analyzed.The proportion of artificial insemination,IVF-ET,polyhydramnios,premature rupture of membranes,pregnancy complicated with diabetes and pregnancy-induced intrahepatic cholestasis was significantly higher in twin group than that of single group.The corresponding proportions in the two groups were statistically different (1.79％ vs.0.16％,1.79％ vs.0.16％,2.79％ vs.1.38％,32.48％ vs.29.65％,19.50％ vs.15.84％ and 2.22％ vs.1.41％,P＜ 0.05).Comparing the neonatal outcomes,the incidence of stillbirth,birth defects and neonatal respiratory distress syndrome in singleton preterm birth group was significantly higher than that of twin preterm birth group (8.68％ vs.2.22％,11.20％ vs.8.52％,15.35％ vs.12.90％,P ＜ O.05).Apgar 1 minute,5 minutes and 10 minutes score was significantly higher in twin group than in the single premature birth group,the difference being statistically significant [(9.43±0.023) min vs.(9.06±0.026) min,(9.85 ±0.013) min vs.(9.69±0.016) min,(9.92±0.011) min vs.(9.81 ±0.014) min,P ＜ 0.05].Conclusion The risk of twin premature birth is significantly higher than that of single fetus.Compared with single premature birth,artificial insemination,IVF-ET,polyhydramnios,premature rupture of membranes,pregnancy complicated with diabetes and intrahepatic cholestasis of pregnancy are more closely related to the twin premature birth.The outcome of twin premature birth is better than that of single birth.