***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Abstract This prospect i ve study evaluated the viability of telbivudine for blocking mother-to-child transmission ( MTCT ) of hepatitis B virus ( HBV ) infection . Pregnant women positive for the hepatitis B surface antigen began telbivudine treatment before 14 weeks of gestation ( i.e. , early ) , between 14 and 28 weeks of gestation ( late ) , or not at all ( control ) . In the late-treatment group , 55 women terminated telbivudine therapy within puerperium . All neonates underwent routine hepatitis B immunoglobulin plus vaccination . Mothers and infants were followed for 7 months after birth . Pregnancy outcomes were similar among the 3 groups . HBV MTCT rates in the early and late treatment and control groups were 0 , 0 , and 4.69 % , respectively . The rates of infant vaccination success among the 3 groups were similar , as were neonatal outcomes including birth weights , asphyxia , hyperbilirubinemia , Apgar score , birth defects , and weight and height at 7 months . Puerperal discontinuation of telbivudine did not increase the alanine transaminase value at 7 months after birth , but increased serum HBV DNA levels , and rates of positive hepatitis Be-antigen .  Telbivudine treatment in HBV-infected pregnant women was associated with lower serum HBV DNA levels and reduced rates of HBV MTCT ; there were no associated changes in pregnancy or neonatal outcomes at birth or 7 months after birth , or in the rate of infant vaccination success . Puerperal drug withdrawal after short-term antiviral therapy will not influence hepatic function , but may increase virus replication This r and omized , double-blind , placebo-controlled study evaluated whether lamivudine given during late pregnancy can reduce hepatitis B virus ( HBV ) perinatal transmission in highly viraemic mothers . Mothers were r and omized to either lamivudine 100 mg or placebo from week 32 of gestation to week 4 postpartum . At birth , infants received recombinant HBV vaccine with or without HBIg and were followed until week 52 . One hundred and fifty mothers , with a gestational age of 26 - 30 weeks and serum HBV DNA > 1000 MEq/mL ( bDNA assay ) , were treated . A total of 141 infants received immunoprophylaxis at birth . In lamivudine-treated mothers , 56 infants received vaccine + HBIg ( lamivudine + vaccine + HBIg ) and 26 infants received vaccine ( lamivudine + vaccine ) . In  placebo-treated mothers , 59 infants received vaccine + HBIg ( placebo + vaccine + HBIg ) . At week 52 , in the primary analyses where missing data was counted as failures , infants in the lamivudine + vaccine + HBIg group had a significant decrease in incidence of HBsAg seropositivity ( 10/56 , 18%vs 23/59 , 39 % ; P = 0.014 ) and in detectable HBV DNA ( 11/56 , 20%vs 27/59 , 46 % ; P = 0.003 ) compared to infants in the placebo + vaccine + HBIg group . Sensitivity analyses to evaluate the impact of missing data at week 52 result ing from a high dropout rate ( 13 % in the lamivudine + vaccine + HBIg group and 31 % in the placebo + vaccine + HBIg group ) remained consistent with the primary analysis in that lower transmission rates were still observed in the infants of lamivudine-treated mothers , but the differences were not statistically significant . No safety concerns were noted in the lamivudine-treated mothers or their infants . Results of this study suggest that lamivudine reduced HBV transmission from highly viraemic mothers to their infants who received passive/active immunization Background To evaluate the efficacy and safety of treating HBV-positive mothers with telbivudine in early and middle pregnancy to prevent mother-to-infant HBV transmission . Methods The subject population comprised pregnant women with chronic hepatitis B ( CHB ; n = 188 ) from January 2013 to June 2015 , with HBV DNA ≥1.0 × 107copies/mL and increased alanine aminotransferase levels . Groups A ( n = 62 ) and B ( n = 61 ) were treated with telbivudine starting at 12 weeks or 20–28 weeks after gestation , respectively . Telbivudine was discontinued at postpartum 12 weeks . Group C ( n = 65 ) received no antiviral . All infants were vaccinated with hepatitis B immunoglobulin ( 200 IU ) and HBV vaccine ( 20 with hepatitis B The maternal HBV DNA levels of the groups were compared . Mother-to-infant transmission of HBV was indicated by the presence of HBsAg in infants 7 months after birth . Results Before treatment , the HBV DNA levels of the 3 groups were similar . Before delivery and 12 weeks after delivery , the HBV DNA levels of groups A and B were similar , but both were significantly lower than that of group C ( P < 0.01 , all ) . No infants in groups A and B were HBsAg-positive , but the infection rate of group C was 18.4 % ( P < 0.01 ) . The HBV infection rate of infants was positively associated with the HBV DNA levels of the pregnant mothers . Conclusion Administration of telbivudine to HBV-infected mothers , started during early and middle pregnancy , completely blocked mother-to-infant HBV transmission . Trial registration The study was registered retrospectively on Janurary 25 in 2016 at Chinese Clinical Trial Registry ( ChiCTR-OPC-16007899 ) Infection of hepatitis B virus ( HBV ) occurs in ~10 % of infants of HBV-infected mothers with positive hepatitis B e antigen ( HBeAg ) after immunoprophylaxis . We aim ed to evaluate the safety and efficacy of telbivudine used during late pregnancy for preventing mother-to-child transmission of HBV . We conducted a multicenter prospect i ve cohort study in 5 hospitals from 2012 to 2014 , which enrolled HBV-infected singleton pregnant women with positive HBeAg . By their choice , women were divided into therapy ( telbivudine 600 mg/day , from gestation 28 - 32 weeks to 3 - 4 weeks postpartum ) and control ( no antiviral agent ) groups . Infants received passive-active immunoprophylaxis and follow-up at the age of 7 - 14 months . Totally , 328 pregnant women were included : 149 in the telbivudine group and 179 in the control group .  Baseline HBV DNA levels were similar in the 2 groups ( 7.43 vs 7.37 log10 IU/mL , P = .711 ) . At delivery , HBV DNA levels in the telbivudine and control groups were 3.80 and 7.26 log10 IU/mL , respectively ( P < .0001 ) . Of the infants , 128 ( 85.9 % ) in the telbivudine group and 156 ( 87.2 % ) in the control group were followed up . No infant in the telbivudine group had chronic infection , while 2 ( 1.28 % ) infants in the control group did ( P = .503 ) . Three ( 2.34 % ) infants in the telbivudine group , but none in the control group , had severe congenital or developmental abnormalities ( P = .090 ) . The data indicate that telbivudine may block perinatal HBV transmission . However , larger studies are required to clarify whether anti-HBV therapy in pregnancy is associated with severe adverse effects in the foetuses and infants BACKGROUND Pregnant women with an elevated viral load of hepatitis B virus ( HBV ) have a risk of transmitting infection to their infants , despite the infants ' receiving hepatitis B immune globulin . METHODS In this multicenter , double‐blind clinical trial performed in Thail and , we r and omly assigned hepatitis B e antigen (HBeAg)–positive pregnant women with an alanine aminotransferase level of 60 IU or less per liter to receive tenofovir disoproxil fumarate ( TDF ) or placebo from 28 weeks of gestation to 2 months post partum . Infants received hepatitis B immune globulin at birth and hepatitis B vaccine at birth and at 1 , 2 , 4 , and 6 months . The primary end point was a hepatitis B surface antigen (HBsAg)–positive status in the infant , confirmed by the HBV DNA level at 6 months of age . We calculated that a sample of 328 women would provide the trial with 90 % power to detect a difference of at least 9 percentage points in the transmission rate ( expected rate , 3 % in the TDF group vs. 12 % in the placebo group ) . RESULTS From January 2013 to August 2015 , we enrolled 331 women ; 168 women were r and omly assigned to the TDF group and 163 to the placebo group . At enrollment , the median gestational age was 28.3 weeks , and the median HBV DNA level was 8.0 log10 IU per milliliter . Among 322 deliveries ( 97 % of the participants ) , there were 319 singleton births , two twin pairs , and one stillborn infant . The median time from birth to administration of hepatitis B immune globulin was 1.3 hours , and the median time from birth to administration of hepatitis B vaccine was 1.2 hours . In the primary analysis , none of the 147 infants ( 0 % ; 95 % confidence interval [ CI ] , 0 to 2 ) in the TDF group were infected , as compared with 3 of 147 ( 2 % ; 95 % CI , 0 to 6 ) in the placebo group ( P=0.12 ) . The rate of adverse events did not differ significantly between groups . The incidence of a maternal alanine aminotransferase level of more than 300 IU per liter after discontinuation of the trial regimen was 6 % in the TDF group and 3 % in the placebo group ( P=0.29 ) . CONCLUSIONS In a setting in which the rate of mother‐to‐child HBV transmission was low with the administration of hepatitis B immune globulin and hepatitis B vaccine in infants born to HBeAg‐positive mothers , the additional maternal use of TDF did not result in a significantly lower rate of transmission . ( Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development ; Clinical Trials.gov number , NCT01745822 . OBJECTIVE To investigate the efficacy of telbivudine on intrauterine hepatitis B virus ( HBV ) infection during the last stage of pregnancy . METHODS 61 pregnant chronic hepatitis B ( CHB ) patients were enrolled and 31 patients were treated by telbivudine 600 mg once daily , 30 patients in the control group were not received antiviral treatment .  Maternal HBV DNA level and the HBsAg positive rate in newborns were investigated . RESULTS The levels of serum HBV DNA in patients treated with Telbivudine were significantly reduced ( t = 19.09 , P less than 0.01 ) . Compared with the control group , serum HBV DNA levels were significantly lower in telbivudine treated patients than those in the control group before parturition ( t = 23.64 , P less than 0.01 ) . The infection rate of 7-month newborns were 0 and 13.33 % ( 4/30 ) , in telbivudine group and control group , respectively ( x2 = 4.29 , probability value less than 0.05 ) . CONCLUSIONS Telbivudine treatment can block intrauterine infection in pregnant chronic hepatitis B patients OBJECTIVE To investigate the effect of high viral loads ( HBV DNA concentration in blood > 2.0 copy/ml ) on the vertical transmission of hepatitis B virus in mothers with HBV DNA positivity . METHOD Forty pregnant women with HBV DNA positivity were divided r and omly , double-blindly into 2 groups : at 28 weeks of pregnancy , one group received oral lamivudine ( 100 mg/d ) and the other received oral placebo . The serum HBV DNA loads were tested at 28 and 40 weeks ' gestation in mothers , and serum HBV DNA , HBsAg , HBeAg and anti-HBs were examined in infants at 12 month follow up . RESULT Thirty-nine infants finished ( one twins ) the follow up , and 2 infants lost ( 5 % ) . Among them 4 infants were confirmed to be HBV infection ( 10 % , 4/39 ) , 2 in the treatment group ( 10 % , 2/20 ) and 2 in the control group ( 11 % , 2/19 ) ( P > 0.05 ) . The serum HBV DNA levels of 40 weeks ' gestation in the treatment group , compared with 
    Output:
    
Using network analysis , any antiviral agent interrupted HBV vertical transmission much more effectively than placebo .
No agent showed significant efficacy different from others , but a strong trend toward significance was found in telbivudine and tenofovir , of which had the highest probability of being ranked the first- or second-best treatment for reducing MTCT of HBV .
The treatment applied in the first and second trimester had a similar efficacy in preventing MTCT .
Compared with the initiation during the third trimester , lower rate of MTCT was revealed when antiviral therapy was administrated before third trimester , ( RR = 0.045 , 95 % CI 0.0053 to 0.20 ) ; a similar effect at delivery on suppressing maternal HBV DNA level and converting serum HBeAg were achieved if the timing of antiviral treatment started prior , but an obvious improvement of normalizing ALT flare was calculated out ; no statistically differences among maternal and fetal safety outcomes were found if mothers received antiviral agents before pregnant 28 weeks .
This network meta- analysis recommended the earlier use of telbivudine or tenofovir , tends to be better to prevent MTCT of HBV in pregnancy with no increased adverse maternal or fetal outcomes