What are my chances of getting pregnant?

Patient: I had sex with my partner last night and the condom came off without us knowing. He finished inside me around 2. I took Plan B around 7. My period hasn’t come in almost 4 months due to high stress from school. He drinks and smokes and do other drugs a lot. What are our chances of getting pregnant?

Doctor: HelloThanks for the querySince you have taken plan B on time and repeat it after 12 hours after the last dose, there is very less chances of you getting pregnant , provided the 4 months of no cycles is not due to an undetected pregnancy and just stress related. There are chances that plan B may fail, but only about 0.5 to 1 % which is a rare possibility. Also consult a gynecologist to get your cycles regular, you may be examined and asked for a few investigations to rule out polycystic ovaries, thyroid and prolactin disorders, etc which are common causes for irregular cycles.Hope this helped