To date, several studies have manifested that high levels of adrenal corticosteroids and oestrogen hormones during pregnancy can lead to increased HBV viraemia. These hormonal and immune function status changes can result in minimal fluctuations in liver function tests. Serum alanine aminotransferase (ALT) tends to increase in late pregnancy and the postpartum period. Peripartum hepatitis flares leading to hepatic decompensation have been reported.Therefore, the investigators aim to detect and observe the immune function status and incidence of hepatitis in pregnant women with chronic hepatitis B virus infection in late pregnancy and the postpartum period.To provide a clinical evidence for the administration of chronic hepatitis B virus infection pregnant women.

In this trial, pregnants who were positivity for serum HBsAg for more than 6 months and HBeAg , HBV DNA >106IU/mL, alanine aminotransferase (ALT) below 35 IU/mL (ULN=40IU/mL) and no received nucleoside analogue antiviral therapy were enrolled into group A, In addition ,the CHB infection pregnants with undetectable HBVDNA were enrolled into group B(control group).In which, all pregnants were chronic HBV infection without compensated cirrhosis,hepatic adipose infiltration,ICP, hypertension ,heart disease, postpartum hemorrhage. None of the mothers were co-infected with hepatitis A,C,D,E,or HIV;syphilis, Epstein-Barr virus.Serum HBV DNA load(Roche, Pleasanton, CA, USA), HBsAg/anti-HBs level, HBeAg/anti-HBe routine blood test, liver function, renal function will be tested piror to delivery and postpartum 2,6,12 weeks. plasmacytoid dendritic cells(pDCs) and natural killer(NK)cells,CD4＋T cells and regulatory T (Treg) cells were detected by flow cytometry. Plasma cytokines Interferon-alpha 2(IFN-α2) / Interferon-gamma (IFN-γ) / Transforming growth factor beta1 (TGF-β1) / Interleukin-2 (IL-2) / Interleukin-6 (IL-6)/Interleukin-10(IL-10) / Interleukin-17A (IL-17A) / tumor necrosis factor-α1(TNF-α1)were measured by Luminex at the above time point except 2 weeks.

Inclusion Criteria:

• pregnants who were positivity for serum HBsAg for more than 6 months and HBeAg , HBV DNA >106IU/mL/undetectable HBVDNA ,alanine aminotransferase (ALT) below 35 IU/mL (ULN=40IU/mL) and no received nucleoside analogue antiviral therapy

Exclusion Criteria:

• compensated cirrhosis,hepatic adipose infiltration,ICP. hypertension ,heart disease. postpartum hemorrhage. pregnants who were co-infected with hepatitis A,C,D,E,or HIV;syphilis,Epstein-Barr virus.

In this trial, pregnants who were positivity for serum HBsAg for more than 6 months and HBeAg , HBV DNA >106IU/mL, alanine aminotransferase (ALT) below 35 IU/mL (ULN=40IU/mL) and no received nucleoside analogue antiviral therapy were enrolled into group A, In addition ,the CHB infection pregnants with undetectable HBVDNA were enrolled into group B(control group).