Autoincrementing option for Pandas DataFrame index

Is there a way to set an option for auto-incrementing the index of pandas.DataFrame when adding new rows, or to define a function for managing creation of new indices?

You can set ignore_index=True when append-ing:

In [1]: df = pd.DataFrame([[1,2],[3,4]])

In [2]: row = pd.Series([5,6])

In [3]: df.append(row, ignore_index=True)
Out[3]: 
   0  1
0  1  2
1  3  4
2  5  6