Risk of mother-to-child transmission after amniocentesis in pregnant women with hepatitis B virus: a retrospective cohort study

BACKGROUND: Amniocentesis is the most widely used invasive prenatal diagnostic sampling technique. However, whether this increases the risk of mother -to -child transmission of infectious diseases remains controversial. OBJECTIVE: This study aimed to determine whether amniocentesis increases the risk of hepatitis B virus infection in infants who received standard prophylaxis, and to assess the related risk factors for mother -tochild transmission in women who underwent amniocentesis during pregnancy. STUDY DESIGN: This retrospective analysis used the clinical data of pregnant women with hepatitis B virus infection at West China Second University Hospital, Sichuan University in 2019. After meeting the inclusion criteria, the participants were divided into 2 groups on the basis of whether they had undergone amniocentesis during pregnancy. The infant hepatitis B virus serologic status was followed 1 to 6 months after completion of immunization. The infant testing positive for hepatitis B surface antigen and negative for Hepatitis B surface antibody indicated mother -to -child transmission of hepatitis B virus. RESULTS: In total, 1764 pregnant women with hepatitis B virus infection were enrolled. Of these, 846 underwent amniocentesis during pregnancy and 918 did not. All offspring received a standardized immunoprophylaxis schedule. The overall mother -to -child transmission rate for hepatitis B virus was 0.6% (5/846) in the amniocentesis group and 0.4% (4/918) in the control group (P=.745). Subgroup analysis showed that the mother -to -child transmission rate in hepatitis B e antigen -positive women was 1.8% (2/111) in the amniocentesis group and 1.0% (2/ 209) in the control group (P=.612). In women with high viral load, the mother -to -child transmission rate was 1.3% (1/78) vs 0.9% (1/107) (amniocentesis group vs control group; P=1.000). In the amniocentesis group, 31 amniotic fluid specimens had an abnormal appearance (bloody or brown). Univariate analysis showed that the mother -to -child transmission rates of these mothers were statistically higher than those of mothers with pale yellow or transparent amniotic fluid (2/31 vs 3/815; relative risk, 17.527 [3.037-101.151]; P=.012). CONCLUSION: Amniocentesis did not increase the risk of mother -tochild transmission of hepatitis B virus in infants who received a standardized immunoprophylaxis schedule, including those with mothers who were hepatitis B e antigen -positive or had a high viral load. However, the abnormal appearance (bloody or brown) of the amniotic fluid obtained during amniocentesis may indicate increased risk of mother -to -child transmission for hepatitis B virus.