Fetal growth restriction (FGR) is a complication commonly associated with several adverse outcomes. Standardized classification of the condition is important not only for the management but also for epidemiological and research purposes. Classification can be based on the onset, if early or late in pregnancy. Specialists agree that the demarcation should be gestational age at diagnosis before or after 32 weeks. Such classification differentiates two phenotypes determined by the severity of placental disease and the adaptive response and deterioration. From a clinical perspective, though, it is helpful to classify small fetuses in stages according to indices or signs that associate with similar risks and prognosis. This approach indicates follow-up intervals, timing of delivery, and other management strategies, depending on the stratification of risk. The application of protocols contributes to optimizing clinical management and outcomes in FGR.
KeywordsFetal growth restriction Classification Early onset Late onset Small for gestational age