What Causes Severe Pain In Lower Left Abdomen A Week After Menstrual Cycle?

Hi, I am 28 year old, married for last two & half year. I get severe pain at lower left abdomen from 13th or 14th day after the menstruation of 5 days & lasting a week. I feel the pain usually in the early morning & it last for around 1 hour every day during those days. After this, within 2 of 3 days menses starts again. What is this & what can be the reason for the pain? This pain was not there before marriage. I had a missed abortion in Nov-09 & then 2 months after I am having this pain. Please help.