** Thanks for contacting HCM with your health concern 1. since she has taken i pill within 9 hours of unprotected sex thus chances of pregnancy are negligible. 2. i pill has three modes of action: - altering the normal menstrual cycle [delaying ovulation] - Inhibiting Ovulation - Irritate the lining of uterus [endometrium] thereby inhibiting implantation 3. To know if i pill is working watch out for following sign: - lighter menstrual flow [withdrawal bleeding after 5-7 days] and visit your doctor/gynecologist for further examination: i. to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately, till then take adequate rest, drink plenty of water and maintain healthy diet.