Welcome to HCM. I pill
is a safe emergency contraceptive
pill. It should be taken in cases of improper use of regular contraceptive pill, contraceptive failure, unprotected intercourse
It should not be used as a regular contraception
device. It is 95% effective if taken within 24 hours. If she took it within 48 hours it is 85% effective, so you need not worry.
Long term use is not suggested and can cause menstrual irregularities, hindrance is egg release and implantion, etc
Usage of regular contraceptive pills is better. Take care.