Study On The Exposure Factors Of Vertical Transmission Of Hbv From Father To Infan

Objeetive: To explore the exposure factors of vertical transmission of HBV from HBsAg-positive father to infant by case-control study in order to provide scientific evidence for paternal-fetal transmission of HBV prevention.Methods: Using HBsAg and HBV-DNA as screening indicators for pregnant women and their husbands from obstetric clinic after gained the consent from June 2009 to June 2010,121 families with HBVM negative or only HBsAb positive and HBV-DNA negative pregnant women,HBsAg positive husbands and their newborns were selected. We collected information of pregnant women,their husbands and their newborns.Blood samples of pregnant women,their husbands,their newborns and some semen samples of husbands were collected for related indicators detection.In case-control study,according to neonatal cord blood HBV-DNA detection,newboms with cord blood HBV-DNA positive were selected as cases,others as controls.The exposure factors of vertical transmission of HBV from HBsAg-positive father to infant were analyzed by univariate and multivariate logistic regression analysis.Results:①The positive rate of neonatal cord blood HBV-DNA was 19.0%(23/121). Univariate analysis showed that paternal serum HBV-DNA positive,HBeAg positive, paternal first class family history and the time of HBV infection were statistically significant; pregnant women's HBsAb negative was statistically significant (P<0.05).Using multiple logistic regression analysis to eliminate the effect of confounding factors, paternal serum HBV-DNA load levels, paternal first class family history and pregnant women's HBsAb negative were still statistically significant (P<0.05). There was dose-response relationship between paternal serum HBV-DNA load levels and neonatal cord blood HBV-DNA positive (trendχ2=60.108,P<0.01). The analysis of ROC curve showed that paternal serum HBV-DNA load level(106copies/ml) is a better demarcation point to forecast the occurrence of vertical transmission of HBV from HBsAg-positive father to infant, because there was a better sensitivity and specificity during forecast.②The positive rate of semen HBV-DNA was 26.9%(14/52); Using univariate and multiple analysis showed that semen HBV-DNA positive was statistically significant(P<0.05);There is a positive rank correlation between semen HBV-DNA and serum HBV-DNA load levels,the load levels of semen HBV-DNA was lower than serum HBV-DNA load levels.③The positive rate of HBsAg in the cord blood specimens was 15.7%(19/121); There was consistency between analysis of cord blood HBV-DNA, Kappa=0.827. It showed that there is an excellent consistency of examination result by using this two methods. Yet the sensitivity of HBsAg positive test is only 78.3% and there were not many samples.So it was inadvisable to substitute HBsAg for HBV-DNA test as the index to screen vertical transmission of HBV from HBsAg-positive father to infant.④There was no significant difference the history of pregnancy between case group and control group;There was no significant difference at pregnancy outcome between case group and control group(P>0.05).Conclusion:①The risk fators vertical transmission of HBV from HBsAg-positive father to infant are paternal serum HBV-DNA load levels,semen HBV-DNA positive ,paternal first class family history and pregnant women's HBsAb negative.There was dose-response relationship between paternal serum HBV-DNA load levels and neonatal cord blood HBV-DNA positive in newbrons. Paternal serum HBV-DNA load level(106copies/ml) is an appropriate index of the occurrence of vertical transmission.②There is a positive rank correlation between the load levels of semen HBV-DNA and serum HBV-DNA.The load levels of semen HBV-DNA is lower than the load levels of serum HBV-DNA.③pregnant women's HBsAb positive is protective factor that can block paternal-fetal transmisson of HBV.④The key to blocing paternal-fetal transmisson of HBV:HBsAg-positive father should receive effective anti-viral treatment before the planned pregnancy, to reduce HBV-DNA load levels of their blood and semen. The HBsAb negative women of child-bearing age shoud be received hepatitis B vaccine before pregnancy.