Cali G, et al. - In high-risk women with placenta previa, the diagnostic accuracy of ultrasound is investigated in detecting abnormally invasive placenta during the first trimester (11-14 weeks of gestation) of pregnancy. This study suggests that AIP can be detected since the first trimester of pregnancy in these women and that ultrasound performed between 11 and 14 weeks of gestation has an overall good diagnostic accuracy for detecting all types of AIP. However, these findings are observed to be applicable only to women with major placenta previa and prior uterine scar.