i had an unprotected sex with my gilr friend on sep 16, 12. in the morning. she took the first pill of postinor 2 at 10:00 PM in the evening and the second pill at 10:00 the next morning on monday. she is expecting to mens on sep 30, 12 but up to now there is no sign of menstration about to start. what could possibly be the cause? for how many days can postinor 2 delay her menstral cycle? thanks in advance and kind regards