Risk factors for hepatitis B infection during pregnancy in a Nigerian obstetric population.

We aimed to assess the risk factors for hepatitis B infection among pregnant women in Enugu, southeast Nigeria. This was a prospective case-control study of risk factors for hepatitis B surface antigen positivity among pregnant women seen in two tertiary health institutions in Enugu, southeast Nigeria. It was carried out over an 8-month period, January - August 2005. Of the 1,499 pregnant women attending the antenatal clinic, 4.6% (n = 69) were seropositive for hepatitis B surface antigen. A total of 35 (50.7%) HBsAg positive women and 71 negative controls were interviewed. The risk factors for HBsAg were present in 71% (n = 25) of the positive cases, while only 27% (n = 19) of the negative cases had risk factors. The significant risk factors for HBsAg positivity were higher mean parity, higher number of sexual partners since sexual debut, polygamy and previous positive history of sexually transmitted diseases (STD) (p < 0.05). The two groups did not differ with respect to presence of tattoo or scarification marks, positive history of jaundice or contact with a jaundiced patient, previous blood transfusion or contact with blood products, intravenous drug abuse or sharing personal instruments (p > 0.05). Screening pregnant women for hepatitis B infection on the basis of presence of risk factors may not effective. Universal antenatal screening for HBsAg, health education aimed at reducing risk factors and immunisation of all newborn and those at risk of hepatitis B is advocated.