Objective-To estimate the cost effectiveness of different antenatal sc
reening programmes for cystic fibrosis. Setting-Antenatal clinics and
general practices in the United Kingdom. Design-Four components of the
screening process were identified: information giving, DNA testing, g
enetic counselling, and prenatal diagnosis. The component costs were d
erived from the literature and from a pilot screening study in Yorkshi
re. The cost of a given screening programme was then obtained by summi
ng the components according to the specific screening strategy adopted
(sequential and couple), the proportion of carriers detected by the D
NA test, and the uptake of screening. Baseline assumptions were made a
bout the proportion with missing information on carrier status from pr
evious pregnancies (20%), the proportion changing partners between pre
gnancies (20%), and the uptake of prenatal diagnosis (100%). Sensitivi
ty analysis was performed by varying these assumptions. Main outcome m
easure-Cost per affected pregnancy detected. Results-Under the baselin
e assumptions sequential screening costs between pound 40000 and pound
90000 per affected pregnancy detected, depending on the carrier detec
tion rate and uptake. Couple screening was more expensive, ranging fro
m pound 46000 to pound 104000. From the sensitivity analysis a 10% cha
nge in the assumed proportion with missing information from a previous
pregnancy alters the cost by pound 4000; a 10%, change in the proport
ion with new partners has a similar effect but only for couple screeni
ng; and cost will change directly in proportion to the uptake of prena
tal diagnosis. Conclusions-While economic analysis cannot determine sc
reening policy, the paper provides the NHS with the information on cos
t effectiveness needed to inform decisions on the introduction of a sc
reening service for cystic fibrosis.