[Monitoring of maternal-fetal hepatitis B virus transmission by molecular hybridization technique].

Maternal venous blood (MB), umbilical blood (UB) and placental tissue (PT) were collected from 40 HBsAg positive mothers and their neonates, and also blood from 17 babies aged 3-6 months old of this group (BB). All samples were determined for hepatitis B virus (HBV) DNA by molecular hybridization technique using Bio-HBV DNA probe. The results showed: HBV DNA positive rate of MB was 35.0%, 47.5% for UB, 75.0% for PT and 29.4% for BB. 32 P-HBV DNA probe was also used to examine MB and PT. The positive rates of HBV DNA were 30.0% and 70.0% respectively. There was no significant difference between the results of the 2 probes. We considered: (1) With the rapid development of HBV detection technique, the detectable rate of intrauterine infection increases accordingly. (2) Besides transplacental infection, other transmission routes might be existed. (3) The detection of HBV DNA in UB, PT and in the blood of babies born by HBV DNA positive mother within 6 months old provides the reliable diagnosis. (4) HBV DNA molecular hybridization is an accurate and sensitive method for the diagnosis of HBV intrauterine infection.