I have this IUD in.

It was painful as all hell when it was inserted, something that made me think of how childbirth must feel, only maybe 1000 less painful, as it was only a second or two as they opened my cervix up to insert the Mirena.

I noticed this strange darkish red-brown discharge right from day one. It lasted, being almost constant, for a month or two, then it appeared when my normal period would have appeared, then stopped a month or two after that. I asked my OB/GYN about it and he said it was just the uterine lining being dry and shriveled by the hormones in the Mirena (that's what it does, it prevents the Uterus from creating an adequit lining for the zygote to embed in, thus preventing pregnancy), and shedding off as it normally would every month.

Now I have no signs of getting my period at all, which I enjoy immensely as last period before I had the IUD put in was so painful, I was awaken by the severe cramps from a dead sleep.

I noticed maybe a minor gain in weight, and a little extra moodiness as my body got used to the hormones. But now I barely even notice it's in, often forgetting about it altogether for weeks at a time.

There have been some problems with it adhering to the uterine wall in some women, and even penetrating and exiting the uterus altogether and floating freely in the abdomen, but those are supposedly very rare occurrences.

The only adverse effect, other than the slight weight gain and mild moodiness, was a strange inability to consume cheese. I'm talking about actual cheese and not mere artificial cheese flavored product. This strange "aversion" as my sis in law calls it, began almost right after I got the Mirena inserted, and has progressed to the point where the mere sight and smell of some cheeses will cause me to go into a fit of heaving.