Preeclampsia: Definitions, screening tools and diagnostic criteria in the supersonic era

Table 2 Biochemical markers predicting preeclampsia

Markers	Ref.	Age of testing	Sensitivity	Specificity
hCG	Jauniaux et al[73]	2nd trimester	72.7%	90%
	Merviel et al[74]	2nd trimester	54.5%	93.5%
Inhibin A	Spencer et al[75]	1st or 2nd trimester	68%	95%
	Florio et al[76]	2nd trimester	38.9%	92.5%
PP-13	Nicholaides et al[77]	1st trimester	90%	90%
AFP	Jauniaux et al[73]	2nd trimester	72.7%	70%
	Kuo et al[78]	2nd trimester	61.5%	47.3%
Activin A	Florio et al[76]	2nd trimester	61.1%	77.5%
	Spencer et al[75]	2nd trimester	63%	95%
PAPP-A	Poon et al[79]	1st trimester	20.5%	95%
	Spencer et al[80]	1st trimester	62.1%	95%

hCG: Human chorionic gonadotrophin; PP-13: Placental protein-13; AFP:α-fetoprotein; PAPP-A: Pregnancy-associated plasma protein A.