I have had mirena iud now for three years. Befor mirena I always very irregular,I was spotting early in the month and now again, but now it s dark brown..its only visible when I wipe... What is causing this? Let me give you a bit of medical background. 4 years ago 4-17-08 i lost a baby I was 4 months pregnant. I had a d&c where they also removed tissue which looked like it had precancerous cells.. On 8-15-08 I became pregnant.my pregnancy was high risk I had preeclamsia. I had an emergency csection at 32 weeks.. Then after 40 days I had mirena inserted.I have no cramping,no pain, just the dark brown discharge with red spots (sometimes)