i had my period on sunday (3 days ago) after 39 days. Please can you help me tell averagely how long my cycle takes, since last three months was 38, last two months was 32, now 39. i often have unprotected sex with my partner, how do i tell when am free and when am ovulating. Please any advice will do. Is there a way to calculate my period accurately to know when am free and not since the number of days in my cycle keeps changing