Pathological examination of the placenta in small for gestational age (SGA) children with or without postnatal catch-up growth

Background/objective: Approximately 10% of small for gestational age (SGA) infants fail to catch up. The relationship between postnatal growth and placental pathology in SGA infants remains unclear. Our aim was to assess the involvement of placental pathology in postnatal growth of SGA infants.Methods: We retrospectively evaluated placental pathology and postnatal growth in single-pregnancy infants born after 37 gestational weeks in our institution, with both birth weight and length below -2 standard deviation scores (SDS) of the normal weight and length. Catch-up was defined as height reaching -2 SDS before the second birthday. Pathology of the placenta was classified into: abnormality due to maternal factors or fatal factors, villitis of unknown etiology (VUE), other abnormalities and no abnormality.Results: Of the 33084 infants, 142 met our criteria and 49 of them had analyzable data. The overall catch-up rate was 84%. Catch-up growth took place in all infants with no placental abnormality and only 57% of infants with abnormality due to fatal factors. There was no significant relationship between catch-up rate and other factors.Conclusion: Placental pathology is associated with postnatal growth in SGA children born at term. Placental abnormality due to fetal factors is related to poor catch-up rate.