The objective of the study was to assess the prevalence and epidemiology of
hepatitis C virus (HCV) infection in pregnant women in the North Thames re
gion, and in the UK in general. Demographic data were linked to neonatal sa
mples prior to anonymization and testing by anti-HCV EIA, and with RIBA 3 c
onfirmation. Risk factors for maternal infection were explored. Area-specif
ic seroprevalence rates were multiplied into population sizes to estimate H
CV prevalence in pregnant women in the UK. A total of 241/126009 samples we
re confirmed anti-HCV positive. and a further 40 were indeterminate, repres
enting a seroprevalence of 0.19-0.22%; 51% of maternal HCV infections were
in UK-born women (71% of the population), and 22% in women from continental
Europe (5% of the population). Among European-born women, HCV prevalence w
as associated with birth in continental Europe, partner not being notified
at birth registration, partner born in a different region to the mother, an
d inner city residence. Four of the 241 anti-HCV positive samples (1.7%) we
re also anti-HIV-1 positive. It was estimated that each year an estimated 1
150 out of 730 000 pregnancies in the UK would involve a woman infected wit
h HCV (uncertainty range 660-1850), a prevalence of 0.16% (0.09-0.25%). On
the basis of reported rates of mother-to-child transmission of HCV, this wo
uld represent approximately 70 paediatric HCV infections per year.