Answer:
The diagnostic code used for her visit 2 will be O24.03.
Step-by-step explanation:
The code O24.03 is basically a billable ICD code which is used to indicate a diagnose of pre-existing diabetes mellitus type 1 in the puerperium ( the time duration of 6 weeks after the birth of the child during which the mother's reproductive organs goes back to the non-pregnant state).
This code has enough details which can be used to specify a medical diagnosis.