Introduction: A small tooth almost killed two people? Recently, at the Sun Yat-sen Memorial Hospital of Sun Yat-sen University, an expectant mother in her third trimester broke the routine and gave birth to a baby by emergency caesarean section under general anesthesia. The culprit was a small rotten tooth. Dental experts remind that pregnant mothers are especially prone to oral health problems. At this time, \”fuss\” must be prepared as early as possible and preventive measures must be taken as soon as possible.