Neonatal gastric aspirates as a predictor of perinatal hepatitis B virus infections.

OBJECTIVE

To elucidate possible routes and predictors of perinatal transmission of hepatitis B virus (HBV).

METHOD

This was a prospective follow-up study. One hundred and forty-seven out of 1762 pregnant women who were screened in the antenatal clinic of a university teaching hospital were HBsAg carriers. Enzyme immunoassay was used for determination of hepatitis B markers. Occurrence of HBsAg in newborns' gastric aspirates, newborns' and infants' blood, and maternal milk samples were determined. Their relationship with delivery routes and duration of the first stage of labor were analyzed by chi square test.

RESULTS

The presence of HBsAg in newborns' gastric aspirates was strongly associated with the acquisition of HBsAg by the babies. There was no correlation between the rate of infant antigenemia and the duration of the first stage of labor, nor did cesarean section decrease the rate of vertical transmission of HBV.

CONCLUSIONS

This is the first report to provide direct evidence for the major role of the oral route in vertical transmission of HBV during delivery. In addition to maternal serum HBeAg, HBsAg status in newborn's gastric aspirates is another important determinant for vertical transmission of HBV.