What is a potential cause of high AFP in a Quad Screen result?

High alpha-fetoprotein (AFP) levels detected in a Quad Screen test can be associated with several factors. Obesity is a potential cause of elevated AFP levels. This is thought to occur due to the altered metabolism of the liver and an increased production of AFP in the context of excess adipose tissue. Additionally, obesity may affect the accuracy of the serum levels measured in the Quad Screen, potentially skewing the results.

Other factors can also contribute to elevated AFP levels, but in the context of the potential answers provided, obesity stands out as a recognized influencer of AFP levels in maternal screening tests.

In contrast, the other factors listed do not result in elevated AFP levels characteristically seen in a Quad Screen. For instance, single gestation typically indicates lower AFP levels compared to multiple gestations, and low estriol would not directly cause high AFP but rather could contribute to a different pattern seen in screening results. Chromosomal abnormalities can alter the AFP levels variably but typically are associated with either low or normal AFP rather than a significant increase alone. Therefore, obesity is the correct answer in this context.