What is the possibility of pregnancy if one has unprotected sex 3 days after cycle ends but no ejaculation but possible precum?

Up to 30% per cycle.: At your young age, ovulation can occur unpredictably and your fertility rate could be as high as 20-30% per cycle. Take Folic Acid 1-5 mg daily and consult with your gynecologist if you are sexually active without planning a pregnancy - contraception with an iud is a great idea but many options exist. Pre-ejaculate contains spermatozoa so it can (and will) get you pregnant without protection.