Abstract

Atypical placental cord insertion (PCI) includes marginal cord insertion (MCI) where the cord is attached close to the placental edge and velamentous cord insertion (VCI) where the cord is attached to the amniotic sac membrane instead of the placenta itself. VCI has been associated with poor pregnancy outcomes. We conducted a systematic review of the literature to determine the association of abnormal PCI with poor pregnancy outcomes. Seventeen studies were included in this review, all of which were assessed as good quality studies. Typical placental cord insertion and MCI were grouped together as non-VCI and compared with VCI in seven studies. Studies in this systematic review reported an association between atypical PCI, with preterm birth, growth restriction, low birthweight (< 2500 g), emergency Caesarean delivery, and stillbirth. Four studies comparing MCI, VCI, and typical PCI separately were included in a separate analysis resulting in a significantly increased risk of emergency Caesarean delivery for women with VCI compared to women with normal PCI. The evidence suggests an association between atypical PCI and emergency Caesarean delivery. However, the number of studies that could be compared with each other was small, which limited the analysis of other poor pregnancy outcomes.