Much of the proteomic research pregnancy has been the area of pre-eclampsia. Studies have shown differences in women with pre-eclampsia compared with women with uncomplicated pregnancies, including differing serum levels of clusterin 34 and ficolin but these were time-of- disease samples. One study 6 showed differences in five proteins at 26 weeks of gestation but these proteins couldnot be identified. Recently the plasma proteome at 20 weeks in women who subsequently developed pre-eclampsia (n 39) was compared (n 357): 39 proteins were identified and two protein clusters identified as fibrinogen gamma-chain and alpha-1-antichymotrypsin accurately classified women at risk of developing pre-eclampsia.