Learning Objectives for this Presentation:
By the end of the presentation participants will be able to describe the epidemiology of hepatitis B surface antigen (HBsAg) positivity among pregnant women residing in New York City (NYC) during 1995-2005.

Background:
Since the introduction of universal hepatitis B vaccination in the U.S. the incidence of hepatitis B has declined. Despite this, from 1995-2005, the rate of HBsAg positive pregnancies in NYC increased. During the same time period, the proportion of HBsAg positive pregnant women who were born in China increased from 30% to 70%. In a similar time period (1990-2000), there was a 63.1% increase in immigration from China, where hepatitis B is endemic.

Objectives:
To describe the epidemiology of HBsAg positivity among pregnant women in NYC (1995-2005)

Methods:
Surveillance data from reported cases of HBsAg positive pregnancies (NYC DOHMH Perinatal Hepatitis B Program, 1995-2005) were analyzed using SASŪ. The number of pregnancies, the birthplace of pregnant women and immigration rates were obtained from NYC Vital Statistics data (1995-2005) and US Census data (1990-2000).

Results:
In NYC, from 1995 to 2005, the annual number of pregnancies decreased from 237,985 to 223,763, however the rate of HBsAg positive pregnancies increased from 612/100,000 to 800/100,000. In NYC, the rate of HBsAg positive pregnancies among women born in the U.S. declined 43%, while the rate among immigrant women increased 48%. From 2000 to 2005, the average HBsAg positive pregnancy rate was 16,327/100,000 among immigrant women born in China, whereas it was 1,113/100,000 among immigrant women born in all other countries combined.

Conclusions:
Immigrant women from highly endemic areas pose a significant risk of perinatal transmission in NYC. The increased rate of HBsAg positive pregnancies in NYC may be attributed to the increase in immigration of women of childbearing age from China. Changes in immigration patterns necessitate continued allocation of resources for perinatal hepatitis B prevention programs.