Chronic placental insufficiency and foetal growth restriction lead to long-term effects on postnatal retinal structure

The aim of this study was to determine the effects of foetal growth restriction on the retina after birth. Foetal growth restriction (FGR) was induced via umbilico-placental embolization (UPE) in ewes from 120 days of pregnancy until term (term ∼ 147 days); controls were not exposed to UPE. Lambs were delivered and raised until 2 years of age when retinas were collected and processed for structural and neurochemical analysis. The foetuses exposed to UPE were hypexemic and at birth were growth restricted. In 2-year-old FGR sheep, the total thickness of the retina and the number of tyrosine hydroxylase immunoreactive dopaminergic amacrine cells were reduced compared to controls (P < 0.05). It is concluded that restricted foetal growth leads to long-term structural and neurochemical changes in the retina. Of particular interest are the alterations to dopaminergic amacrine cell numbers, as alterations in this population may affect contrast sensitivity and have implications for the alterations in vision observed in very low birthweight infants.