Abnormal Placentation

Abstract

Placental disorders such as placenta previa, placenta accreta, and vasa previa are all associated with vaginal bleeding in the second half of pregnancy. They are also important causes of serious fetal and maternal morbidity and even mortality. Moreover, the rates of previa and accreta are increasing, probably as a result of increasing rates of cesarean delivery, maternal age, and assisted reproductive technology. The routine use of obstetric ultrasonography as well as improving ultrasonographic technology allows for the antenatal diagnosis of these conditions. In turn, antenatal diagnosis facilitates optimal obstetric management. This review emphasizes an evidence-based approach to the clinical management of pregnancies with these conditions as well as highlights important knowledge gaps.

Pregnancy, birth, and infant outcomes by maternal fertility status: the Massachusetts Outcomes Study of Assisted Reproductive Technology

“…Risks for abnormal placentation include factors more common among subfertile and infertile women: older maternal age, endometrial damage and uterine scarring, and short interval between prior cesarean delivery and subsequent pregnancy (56). Studies have confirmed a higher frequency of abnormal placentation in pregnancies conceived through both ovulation induction (46) and IVF (46–48).…”

Detecting Accuracy of Three Dimensional Power Doppler (3DPD) Vascular Indices for Prenatal Diagnosis of Morbidly Adherent Placenta in Patients with Placenta Previa

“…Recently, the term "morbidly adherent placenta" (MAP) has been more frequently used to describe abnormal implantation of the placental villi into the uterine wall [2]. It is histopathological term-occurs when the placenta fails to detach from the wall of the uterus due to abnormal implantation at the basal plate [3].…”

Preoperative cystoscopy could determine the severity of placenta accreta spectrum disorders: An observational study

“…10,13 Despite obstetric ultrasonography being the standard for PAS diagnosis, the reported accuracy of ultrasonography varies greatly between facilities, experts and even nations. 14,15 Magnetic resonance imaging (MRI) is sometimes used but has more variable accuracy, with higher costs and fewer radiology experts in PAS. 14 Unfortunately, disease severity can often only be assessed definitively at the time of surgery and ultimately diagnosed by histopathology.…”

“…14,15 Magnetic resonance imaging (MRI) is sometimes used but has more variable accuracy, with higher costs and fewer radiology experts in PAS. 14 Unfortunately, disease severity can often only be assessed definitively at the time of surgery and ultimately diagnosed by histopathology. Additional methods to evaluate the presence and/or severity of disease prior to surgery are critical for improving maternal outcomes.…”