Hi Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern... Yes you have slight chances of pregnancy despite taking unwanted 72. However chances of your periods delayed is way more than pregnancy. Delay in periods is a common side-effect after intake of an emergency contraceptive pill like Unwanted 72. The delayed periods are due to effect of high dose of levonorgestrel hormone in Unwanted 72 pill which disrupts your normal menstruation & causes delayed periods. Your periods may be delayed for 1-2 cycles. An emergency contraceptive pill prevents pregnancy by inhibiting implantation of fertilized egg on to uterus. It is 95% successful if taken within 24 hours of having sex. As you had taken the emergency contraceptive pill after a hour of sexual intercourse, pregnancy possibility should be very less. An emergency contraceptive should not be used as regular method of contraception.Emergency contraceptive pill is less effective & has higher side effects than regular method of contraception. Next time use regular contraceptive pill or condoms for prevention of unwanted pregnancy. You should also undergo a pregnancy test to rule-out pregnancy possibility, however chances of that should be very less. Refer to a gynaecologist for more queries Don t worry you would be fine Hope this information helps