Placental growth from the first to the second trimester of pregnancy in SGA-foetuses and pre-eclamptic pregnancies compared to normal foetuses.

The aim of this study was to determine placental growth between 12-22 weeks in normal pregnancies compared to pregnancies complicated by foetal SGA and maternal pre-eclampsia (PE). The placentae of 1199 women were measured 3D sonographically at 12, 16 and 22 weeks of gestation. Placental volume growth was then calculated. Neonatal birthweight, birth centile and the occurrence of pre-eclampsia were recorded in every woman and correlated with placental growth (four groups: normals, SGA, PE, SGA+PE). SGA-placentae are already smaller at 12 weeks but then develop in a similar way to normal placentae. PE placentae are slightly, but significantly, larger at 12 weeks, grow rapidly until 16 weeks and then stop growing normally between 16 and 22 weeks. If SGA goes together with PE, both placental volume (PV) at 12 weeks as well as growth is reduced significantly. Nevertheless, placental growth between week 12 and 22 is too heterogeneous to justify using this method as a clinical tool, but it can provide new information on placental physiology underlying unfavourable obstetric outcomes.