Hi, I am 19 years old, 45 kg, 154 cm. I think I have an irregular menstruation cycle. For example. My period started May 4, 2011 - May 9, 2011. (last month) and this month it started last June 9, 2011 and not June 4. So that s considered as irregular cycle, right? I am sexually active and I really would want to know when is it safe to have a sexual intercourse with my partner without worrying of any unwanted pregnancy? Thank you very much!