**Core Concept**
Placenta accreta is a serious pregnancy complication where the placenta grows too deeply into the uterine wall, potentially leading to severe bleeding. It's essential to understand the risk factors and causes of placenta accreta to prevent and manage this condition effectively.

**Why the Correct Answer is Right**
Placenta accreta is often associated with conditions that alter the normal uterine-placental interface, such as prior uterine surgery (e.g., cesarean sections), placenta previa, and multiple gestations. However, some factors are less commonly linked to placenta accreta. For example, **Option A: Maternal age > 35 years** is a risk factor, but not as strongly associated as other conditions like prior uterine surgery.

**Why Each Wrong Option is Incorrect**
* **Option B: Placenta previa** is a common cause of placenta accreta, as both conditions often occur together and increase the risk of severe bleeding.
* **Option C: Multiple gestations** are also a risk factor for placenta accreta, as they can disrupt the normal uterine-placental interface and lead to abnormal placentation.
* **Option D: Uterine anomaly (e.g., bicornuate uterus)** is a known risk factor for placenta accreta, as it can alter the normal uterine shape and increase the risk of abnormal placentation.

**Clinical Pearl / High-Yield Fact**
When managing a patient with a history of prior uterine surgery, it's essential to be aware of the increased risk of placenta accreta and to perform regular ultrasound assessments to monitor placental growth and identify potential complications early.

**Correct Answer: A. Maternal age > 35 years**