Inpatient Obstetric Nurse (NCC) Practice Exam

Which of the following factors is associated with an increased size of the placenta?

1. Shortened interpregnancy interval

2. High maternal BMI

3. Maternal smoking

4. Previous cesarean delivery

The correct answer is: High maternal BMI

The association between high maternal Body Mass Index (BMI) and an increased size of the placenta is well-documented in the literature. Women with a higher BMI tend to have larger placentas, which can be attributed to a variety of factors including increased blood flow and nutrient supply to the placenta due to maternal obesity. The placenta is an organ that supports the fetus through the delivery of nutrients and oxygen, and a higher maternal weight often reflects an increased capacity for placental growth. In contrast, other factors listed, such as shortened interpregnancy intervals and maternal smoking, are typically associated with smaller placental sizes or adverse pregnancy outcomes. Shortened interpregnancy intervals can lead to inadequate maternal nutrient stores, potentially resulting in a less robust placental growth. Maternal smoking is known to restrict blood flow and oxygen availability to the placenta, contributing to a smaller placenta and increased risks for various complications. Previous cesarean deliveries do not have a direct correlation with increased placental size, as the size of the placenta usually depends more on maternal health and metabolic conditions rather than surgical history. Thus, high maternal BMI is the most directly linked factor to an increased size of the placenta.