Effect of delayed cord clamping on preterm infants with gestational age ＜32 weeks: a meta-analysis / 中华围产医学杂志

ABSTRACT

Objective To evaluate the effects of delayed cord clamping (DCC) on preterm infants with gestational age ＜32 weeks.Methods Literatures from January 1,1990 to April 30,2013 in Cochrane library,PubMed,EMBASE,China Academic Journal Network Publishing Database,Wanfang Medical Database and VIP Database were searched.Randomized controlled trials (RCT) of DCC in preterm infants with gestational age ＜32 weeks were screened and evaluated.DCC was defined as cord clamping in 30-90 s after delivery,and early cord clamping (ECC) (＜30 s) was as the control.Rev Man 5.1.0 was used for statistical analysis.Mean difference (MD) and 95％CI were used for continuous data while OR and 95％CI were for categorical data.Results Nine studies (11 articles) involving 373 infants were included.Compared with ECC,DCC improved hematocrit (MD=4.19,95％CI2.97-5.40,Z=6.74,P＜0.000 01),blood volume (MD=11.70,95％CI6.02-17.38,Z=4.04,P＜0.0001) and mean arterial pressure of preterm infants with gestational age ＜32 weeks (MD=3.11,95 ％CI1.30-4.92,Z=3.37,P=0.0008),decreased the usage of volume expansion for hypotension (OR=0.32,95％CI0.11-0.98,Z=2.05,P=0.04) and the incidence of necrotizing enterocolitis (OR=0.48,95％CI0.25-0.92,Z=2.22,P=0.03).Meanwhile,DCC had no influence on the peak bilirubin concentration,the incidence of sepsis,patent ductus arteriosus,retinopathy and intracranial hemorrhage,also no influence on neonatal mortality on dcscharge,mental developmental index and psychomotor developmental index at seven-month old.Conclusions DCC might be a safe procedure to improve prognosis of preterm infants less than 32 weeks' gestational age.However,due to small sample size and lack of data on follow up,it is necessary to launch clinical trials with higher quality and larger scale to further evaluate the effect and safety of DCC.