Circulating SPINT1 in the second trimester is reduced among pregnancies that ends in low birthweight neonates: cohort study of 2006 pregnancies

Serine peptidase inhibitor Kunitz type 1 (SPINT1) is a circulating protein with possibly the strongest association with low birthweight and placental insufficiency to be reported. Low plasma SPINT1 levels at 36 weeks of gestation (P=2.7 × 10−13; Australian cohort1) and 26 to 34 weeks of gestation (validation cohorts in the United Kingdom1 and Singapore2) were strongly linked with the birth of a neonate with a birthweight of <10th percentile. Its biomarker performance seemed to consistently outperform the circulating placental growth factor.