Hi Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern... Yes pregnancy is possible through precum or pre-ejaculatory fluid, but it is rare. Pre-ejaculatory fluid is a secretion of cowper gland which occurs before ejaculation in males & research shows that this may contain some sperms in it. Most of these sperms are however dead or non-motile. There may be some sperms left over penis from previous ejaculation too, which could also cause pregnancy. But as you have taken emergency contraceptive pill 3 days after the intercourse. Emergency contraceptive pill should be taken as early as possible to be more effective in preventing pregnancy. If you ahve taken the pill after 72 hours of sexual intercourse, it might not be effective in pregnancy prevention. So all togethar slight chances of pregnancy are there in you. You should do a pregnancy test, to rule-out pregnancy possibility if your next expected period is delayed or missed. Therefore one should wear condom before any penetration to be protected from unwanted pregnancy. You should also avoid taking emergency contraceptive pill as these are less effective & have more side effects than other methods of contraception. Hope this information helps Good luck