METHODS
This was a case-control study involving analysis of serum PLGF, sFLT-1, IL-6, TNF-α, endothelin and VCAM levels in stored samples (-80oC) obtained at 11-13 weeks’ gestation from 650 singleton pregnancies complicated by CH and 142 normotensive control subjects who attended King’s College Hospital (London, UK) for pregnancy care between January 2011 and September 2018. Gestational age was determined from measurement of fetal crown-rump length.14