Circulating soluble fms-like tyrosine kinase-1 is placentally derived in normal pregnancy: First in vivo evidence

Abstract

Circulating sFlt-1 increases significantly in pregnancy compared to the non-pregnant state and even more so in the event of preeclampsia. We set out to determine if circulating sFlt-1 is placentally derived in normal pregnancy. Paired uterine and peripheral vein samples were collected at time of caesarean section. A follow up peripheral sample was collected in the postpartum period. There was a significant sFlt-1 gradient between uterine and peripheral veins. sFlt-1 levels dropped significantly when the placenta has been removed, i.e. postnatally. This is in keeping with the placenta being the main site of sFlt-1 production in normal pregnancies.

Keywords: Placenta; Preeclampsia; Pregnancy; Uterine vein; sFlt-1.