Bandl’s ring is developed in a primigravida who is in labour. It is associated with the following condition:
**Core Concept**
Bandl's ring is a pathognomonic sign of obstructed labor, characterized by a segment of the uterus that is separated from the rest of the uterine muscle due to prolonged uterine contractions. This phenomenon occurs when the uterus is subjected to prolonged and intense contractions, leading to a localized area of ischemia and necrosis.
**Why the Correct Answer is Right**
The development of Bandl's ring is a consequence of the "rupture theory" of obstructed labor. In this scenario, the uterus contracts around the presenting fetal part, leading to a localized area of ischemia and necrosis. As a result, the affected segment of the uterus becomes separated from the rest of the uterine muscle, forming a characteristic "waist" or "ring" appearance. This phenomenon is often associated with conditions that lead to prolonged and intense uterine contractions, such as cephalopelvic disproportion.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because cervical dystocia is a condition characterized by a narrow cervix that hinders fetal descent, but it is not directly associated with the development of Bandl's ring.
**Option B:** This option is incorrect because placenta previa is a condition characterized by the placenta implanting in the lower uterine segment, but it is not directly associated with the development of Bandl's ring.
**Option C:** This option is incorrect because uterine atony is a condition characterized by a failure of the uterus to contract after delivery, but it is not directly associated with the development of Bandl's ring.
**Clinical Pearl / High-Yield Fact**
It is essential for healthcare providers to recognize the signs of obstructed labor, including the development of Bandl's ring, as prompt intervention is crucial to prevent maternal and fetal morbidity.
**Correct Answer: C. Cephalopelvic disproportion.**