Mechanisms of solute transfer across the human placenta: effects of intrauterine growth restriction

Intrauterine growth restriction (IUGR) has a variety of causes and this article will focus on those which may be related to pathology of the trophoblast – so-called placental insufficiency. The main message we wish to convey is that the aetiology of these cases of IUGR is not solely related to abnormalities of uterine or umbilical bloodflow but is also likely to involve specific placental transport mechanisms. Amino acid transporters, in particular, are implicated.