OBJECTIVETo explore the impact of maternal hepatitis B surface antigen (HBsAg) carrier status on the occurrence of preterm birth.

METHODSWe analyzed pregnancy-related complications, outcomes and fetal growth index in 188 HBsAg positive singleton pregnant women during the period of May 2009 to July 2011, with 265 HBsAg-negative women with singleton pregnancies in the same period serving as controls.

RESULTSThe HBsAg-positive pregnant women showed a significantly higher incidence of placenta praevia than the control group (2.66% vs 0%, P=0.03), and the incidence of preterm delivery (<37 weeks) was also significantly higher in HBsAg-positive group (12.23% vs 6.04%, P=0.02). The incidences of gestational hypertension, preeclampsia, gestational diabetes mellitus, abnormal glucose tolerance, premature rupture of membranes, cesarean delivery, and postpartum hemorrhage showed no significant differences between the two groups (P>0.05), nor did the fetal birth weight, height, head circumference or Apgar scores at 1, 5, and 10 min (P>0.05). Logistic regression identified HBsAg positivity, abnormal ALT, placenta praevia, and severe preeclampsia as the risk factors for preterm delivery.

CONCLUSIONHBsAg carrier status can increase the risk of preterm delivery in pregnancy, but it does not seem to affect the fetal growth.