Thirty-five case control or cohort studies (138,571 women; 3,654 (2.6%) developed pre-eclampsia) were included in the review; there were only two prospective studies. Quality assessment indicated that none of the studies reported on reference tests and most studies did not blind assessors to index test results.
Serum markers: For ADAM12, only one study (of five) reported a detection rate of 38% (95% CI 27% to 50%) for unspecified pre-eclampsia. Fβ-hCG (10 studies) was not shown to be a predictive marker of pre-eclampsia.
For inhibin A and activin A, one of five studies reported detection rates of 35% for inhibin A and 20% for activin A.
Five studies reported PP13 levels in early onset pre-eclampsia; detection rates ranged between 37% and 80%. Detection rates for PIGF in the first trimester were 41% and 59% for early-onset pre-eclampsia; for late onset pre-eclampsia the rate was 33%.
Eight studies assessed PAPP-A. Four studies reported detection rates that ranged from 22% to 43% in early-onset pre-eclampsia.
Uterine artery Doppler ultrasound: Abnormal uterine artery waveforms seemed to be a good predictor of pre-eclampsia but detection rates for early onset varied between 29% and 83% and for late onset varied between 5% and 62%.
Maternal characteristics: Detection rates for maternal characteristic alone ranged from 23% to 56% in early, late and unspecified pre-eclampsia (15 studies).
Combined screening: For combinations of two markers, the best detection rate was reported for the combination of PP13 and uterine artery Doppler ultrasound (90%; one study). For the combination of more than two markers, detection rates ranged from 38% to 100% with the best rates reported for the combination of five markers (Inhibin A, PIGF, PAPP-A, ultrasound and maternal characteristics).