Final answer:
Precocious menstruation is referred to as precocious puberty, where a child starts developing signs of puberty at an earlier age than usual.
Step-by-step explanation:
Precocious menstruation is not reported with a specific medical code. However, it is referred to as a condition known as precocious puberty.
Precocious puberty is when a child starts developing signs of puberty, such as breast enlargement and menstruation, at an earlier age than usual. It is important to consult with a healthcare professional if a child is experiencing early menstruation to determine the underlying cause and appropriate treatment.