The extremism usually consists in lack of reason. 

Nobody denies that women have the right to decide. The issue is when they should decide and about what. 

Only prior to pregnancy can one decide whether to become pregnant.

Once pregnant, one can only decide whether to kill or not to kill the unborn human being. In this case the decision involves not only the 'self' but all involved: the woman, the unborn human being and the one who collaborated in creating the unborn human being.   
 
Extremism in this issue is rooted in the inability or unwillingness to accept the complexity of the second situation, and subordinate everything  and everyone to the needs and preferences of the 'self', of the woman.