Perinatal transmission of @entity1956 occurs if the mother has had @entity1956 during late pregnancy or in the first months postpartum, or if the mother is a chronic HB antigen carrier. Vertical transmission from chronic carriers exceeds 90% and accounts for up to 40% of the world chronic carriers in endemic areas. @entity99 in pregnancy is not associated with increased abortion rate, @entity2209 , or @entity600 . However, prematurity seems to be increased if @entity99 is acquired in the last trimester. Sixty percent of pregnant @entity1 who acquire @entity1956 at or near delivery will transmit the HB virus to their offspring. Although infection is rarely symptomatic, 70 to 90% of the babies will remain chronically infected into adult life and be prone to @entity82 and @entity157 . Because of such high risks and the safety and efficacy (seroconversion 90 to 100%) of HB vaccine in preventing @entity1956 , it is recommended that HB vaccine be given to pregnant @entity1 at high risk. However, its safety to the fetus is not well documented. Only one @entity1 study reports the safety and efficacy of Heptavax, but only when administered (to 72 pregnant @entity1 ) in the last trimester of pregnancy when @entity2241 cannot occur. We report pregnancy outcome in ten @entity1 , @entity283 care personnel or @entity1 traveling to endemic areas exposed to the vaccine during the first trimester of pregnancy. No @entity154 were observed and all the @entity1 are physically and developmentally normal for their ages at 2 to 12 months. Although small, this cohort suggests safe use of the vaccine in early pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

XXXX vaccine in pregnancy: maternal and fetal safety.

@entity1 :: ('9606', 'Species') :: ['women', 'human', 'patients', 'infants'] @entity154 :: ('MESH:D000013', 'Disease') :: ['congenital abnormalities'] @entity82 :: ('MESH:D005355', 'Disease') :: ['cirrhosis'] @entity1956 :: ('MESH:D006509', 'Disease') :: ['acute HB infection', 'acute HB infections', 'hepatitis B (HB) virus', 'HB infection'] @entity283 :: ('OMIM:603663', 'Disease') :: ['mostly health'] @entity2209 :: ('MESH:D050497', 'Disease') :: ['stillbirth'] @entity600 :: ('MESH:D000014', 'Disease') :: ['congenital malformation'] @entity157 :: ('MESH:D006528', 'Disease') :: ['hepatocellular carcinoma'] @entity99 :: ('MESH:D056486', 'Disease') :: ['Hepatitis', 'hepatitis'] @entity2241 :: ('MESH:D005315', 'Disease') :: ['embryopathy']
@entity1956 :: (MESH:D006509,Disease) :: ['Hepatitis B']
