What is the purpose of alpha-fetoprotein testing during pregnancy?

Alpha-fetoprotein (AFP) testing during pregnancy is primarily used to screen for neural tube defects in the developing fetus. Elevated levels of AFP in maternal serum can indicate potential abnormalities, such as spina bifida or anencephaly, which are types of neural tube defects. This screening is typically performed during the second trimester and helps identify pregnancies that may warrant further testing, such as ultrasound or amniocentesis, to confirm diagnosis and assess fetal health.

In contrast, the other options do not align with the primary purpose of AFP testing. Cardiovascular disorders are typically evaluated through different screening methods, while placental function is monitored through ultrasounds or specific blood tests that measure placental markers, rather than AFP. Additionally, maternal pre-eclampsia is assessed through blood pressure measurements and urine tests for protein, not through alpha-fetoprotein levels.