OBJECTIVES: To evaluate the association between maternal hepatitis B virus (HBV) infection and congenital abnormalities following assisted reproduction (ART).

METHODS: This is a population-based retrospective cohort study using data from Xiamen registry of pregnant women and offspring (REPRESENT), which was established at 2006 and collecting healthcare data from pregnant women and their offspring across all maternity departments in Xiamen city, a coastal city located in southeast China with 4.11 million permanent residents. Up to March 2019, REPRESENT has accumulated data concerning 761194 pregnancies and 765905 newborns. 9716 pregnancies undergoing ART and status of HBsAg and HBeAg were screened at the first antenatal visit during January 2014 to March 2019.

RESULTS: 7032 pregnancies with 8939 newborns were finally included. The prevalence of maternal HBsAg+, HBsAg+HBeAg+, and HBsAg+ HBeAg- examined at the first trimester were 11.35% (95% CI 10.6-12.1%), 2.55% (2.1-3.0%) and 9.46% (8.7-10.2%), respectively. Total fetal abnormalities and non-chromosomal abnormalities incidence at newborn level was 2.63% (2.3-3.0%) and 2.38% (CI 2.1-2.7%). Compared to HBsAg- group, multivariable analyses indicated maternal HBsAg+ significantly increase the risk of congenital malformations of kidney and cleft palate with adjusted relative risk (aRR) of 4.31 (1.27-14.64) and 7.86 (1.57-39.46) after adjusted maternal age. Similarly, compared to HBsAg-HBeAg- group, maternal HBsAg+HBeAg- could increase the risk of congenital malformations kidney and cleft palate with aRR of 4.23 (1.08-16.59) and 6.38 (1.07-38.09). Compared to HBsAg-HBeAg- group, higher incidence of congenital malformations of eye, ear, face, neck was presented in HBsAg+HBeAg+ group, with aRR of 27.38 (1.56-481.88). No significant association was found between total non-chromosomal abnormalities incidence and either HBsAg or HBeAg positivity.

CONCLUSIONS: The prevalence of maternal HBsAg+ was high in Chinses pregnant women undergoing ART. Maternal HBsAg+ could increase the risk of several specific categories of congenital malformations following ART (i.e., congenital malformations of kidney and cleft palate).