**Core Concept**
Fetal blood loss, also known as fetal exsanguination, is a life-threatening complication that can occur during pregnancy due to the rupture of fetal blood vessels. This condition is often associated with vasa previa, a rare but serious condition where fetal blood vessels are exposed and unsupported in the lower uterine segment.

**Why the Correct Answer is Right**
Vasa previa is characterized by the presence of fetal blood vessels that are unsupported by the placenta or umbilical cord, making them susceptible to rupture. This condition can lead to significant fetal blood loss, which can result in fetal distress, growth restriction, or even fetal demise. The risk of vasa previa is higher in cases of multiple gestations, placenta previa, and cervical cerclage.

**Why Each Wrong Option is Incorrect**
* **Option A:** Uterine rupture is a severe condition that can lead to significant maternal morbidity and mortality, but it is not directly associated with fetal blood loss.
* **Option B:** Placenta previa refers to the abnormal implantation of the placenta in the lower uterine segment, which can lead to bleeding in the mother, but it is not typically associated with fetal blood loss.
* **Option D:** Circumvallate placenta is a condition where the placental membranes are folded inward, creating a placental edge that can lead to bleeding in the mother, but it is not directly associated with fetal blood loss.

**Clinical Pearl / High-Yield Fact**
Vasa previa is often associated with other risk factors, such as a previous uterine surgery, multiple gestations, or a previous stillbirth. It is essential to identify these risk factors and perform a thorough ultrasound examination to detect vasa previa early in pregnancy.

✓ Correct Answer: C. Vasa previa