Background <p>Management and outcomes in women with placenta accreta spectrum grade 3 are rarely reported from population-based studies. The objective of this study is to describe profiles, management, and outcomes, of women with placenta accreta spectrum (PAS) grade 3 from three multiperiod studies.</p> Methods <p>This analysis used data from three multiperiod population-based cohort studies from the United Kingdom (UK) (May 2010–April 2011), France (November 2013–October 2015), and Italy (September 2014–August 2016) to compare the management and outcomes of women with grade 3 PAS. The main outcome measures were postpartum hemorrhage (PPH) ≥ 3000 mL, blood transfusion ≥ 4 units, and other severe maternal complications (death, damage to bowel or urinary tract).</p> Results <p>This study included 39 women with PAS grade 3 in the UK, 51 in France, and 34 in Italy, a total of 124 women. PAS was suspected before birth in 59% of the UK cases, 88% in France, and 82% in Italy (<i>P</i> &lt; .01). Conservative management was attempted only in the UK (38%) and in France (61%). PPH ≥ 3000 mL occurred in 54% of the UK women, 25% in France, and 12% in Italy (<i>P</i> &lt; .01); 67% in the UK, 47% in France, and 41% in Italy received blood transfusion ≥ 4 units (<i>P</i> = .06). The final (immediate and secondary) hysterectomy rate differed significantly between the three countries: 69% in the UK, 57% in France, 100% in Italy (<i>P</i> &lt; .01).</p> Conclusion <p>Maternal outcomes in women with grade 3 PAS varied between the three periods and countries, alongside the evolution in prenatal screening and peri-operative management.</p> Trial registration <p>For the UK: reference number: RP-PG-0608-10038. For France: reference number: AOR12156. For Italy: reference number: Port. PRE-839/13</p>