ARF6 and fetal growth restriction: In most obstetric populations, including women attending our hospital, there is a clear link between pre-eclampsia, intrauterine growth restriction and other risk factors for preterm delivery [43] and alterations in the ARF6 pathway may be a reflection of underlying pathology, however in this study we did not have enough PT-NIL samples to carry out multivariable analysis to assess the contribution of each independent risk factor.