The most common cause of FGR is placental disease, which tends to have two main clinical manifestations
– early and late
- Early onset FGR is often associated with reduced villous cross-sectional vascular area of the placenta which results in a perfusion defect and elevated umbilical artery (UA) blood flow resistance. This type of FGR typically develops in mid-trimester and presents with an SGA fetus and abnormal UA Doppler 8
- Late onset FGR is more common than early onset disease, usually develops after 32 weeks and is associated with villous immaturity and other pathologies producing a placental diffusion defect where reduction in villous cross-sectional area is often below the threshold detectable by UA Doppler 9.
8. Turan OM, Turan S, Gungor S, Berg C, Moyano D, Gembruch U, Nicolaides KH, Harman CR, Baschat AA.
Progression of Doppler abnormalities in intrauterine growth restriction. Ultrasound Obstet Gynecol; 2008: 32: 160-67. https://doi.org/10.1002/uog.5386
9. Figueras F, Gardosi J. Intrauterine growth restriction: new concepts in antenatal surveillance, diagnosis, and management.
Am J Obstet Gynecol. 2011 Apr;204(4):288-300. DOI: https://doi.org/10.1016/j.ajog.2010.08.055