PLACENTA ACCRETA:

Occurence:

• Abnormal attachment of the placenta through the uterine myometrium as a result of defective decidual formation (absent Nitabuch’s layer).

Grades of abnormal placental attachment according to the depth of invasion:

• In this condition, the decidua basalis is absent and

1. Placental villi are attached to the myometrium in placenta accreta
2. Invade the myometrium in placenta increta
3. Penetrate through the myometrium & extend to the uterine serosa in placenta percreta

• The abnormal adherence may involve all of the cotyledons (total placenta accreta), a few to several cotyledons (partial placenta accreta), or a single cotyledon (focal placenta accreta).
• Two-thirds of patients with this complication require hysterectomy.

 Risk factors:

• Patients with a history of uterine surgery are at greatest risk of developing an accreta.
• In fact, those with a prior cesarean section carry a 25% risk.
•  placenta previa in the presence of a uterine scar
• Others –  prior uterine surgery,  endometrial ablation, Asherman syndrome, uterine leiomyomata,

Diagnosis

• Doppler USG– helpful in diagnosis.
• Confirmed only after delivery.