A Case of Undiagnosed Placenta Increta Originating From a Demised Twin in the Second Trimester.

Placenta accreta spectrum (PAS) presents a significant risk of maternal morbidity and mortality, in large part due to the potential for massive hemorrhage at time of delivery. Recently, multiple gestations have been shown to be an independent risk factor for PAS, especially in the setting of other major risk factors. Importantly, antenatal detection of PAS in twin pregnancies has been shown to be suboptimal when compared to singleton pregnancies. Here, we present a case of postpartum hemorrhage and unplanned cesarean hysterectomy due to an undiagnosed placenta increta, which originated from the placenta of a demised twin in the second trimester. This case underscores the importance of thorough prenatal monitoring and evaluation for PAS, especially in multifetal gestations with additional risk factors. It also highlights the need for heightened awareness among healthcare providers to mitigate risks associated with PAS in twin pregnancies. Early detection and multidisciplinary collaboration are crucial in optimizing outcomes for both mothers and infants in such complex obstetric scenarios.