Hi doctor, does pre cum on underpants can cause pregnancy and my periods used to come after every 28 days but 5 days up and ive been eating junk all the time tell me if im pregnant or is it cause of eating junk?

Unless you have actual intercourse you need not worry about pregnancy. Use contraception to avoid it. Irregular periods sometimes occur, and if it continues consult with your OBGYN.

Precum on underpants does not caue pregnancy. Sperms have to enter inside the vagina to do so. Occ periods can be late or irregular. I do not think you are pregnant- from this info. If still worried get a preg. test