If a woman makes an oath to Allah saying that she will undergo female circumcision and if she breaks her oath she will become a kafir forever.
Does she become a kafir if she has changed her mind and does not want to undergo circumcision?
Female circumcision is not an Islamic pratice. Thus it would not be considered a valid oath to begin with. If someone does take an oath of something that is not considered permissile in Islam then they must break their oath and give Kaffarah. She will not become Kafir by not undergoing circumcision due to her oath. As a matter of fact she would be doing the right thing by not doing what she had taken the oath for due to her ignorance.
Kaffarah of breaking an oath is to feed one time meal to 10 poor people.
And Allah knows best.
Mufti Ikram ul Haq
Fatwa Center of America