Amniotic fluid contamination refers to the entry of meconium into amniotic fluid, resulting in abnormal amniotic fluid composition. Fetal distress can be caused by umbilical cord entanglement, placental abruption, and hypertensive disorders of pregnancy, resulting in contamination of the amniotic fluid by fetal feces. Or amniotic cavity infection, pathogenic microorganisms, pus, etc. into the amniotic fluid to cause contamination. Normal full-term amniotic fluid is a colorless, transparent or slightly chaotic liquid, neutral or weakly alkaline, and can have fetal fat and other suspended matter. Amniotic fluid contamination is caused by the discharge of meconium, which turns the amniotic fluid green, cloudy, viscous and less in volume.