I was previously on hormonal birth control (Aviane, very low dose) and felt as though the hormones in the Mirena were less affective than even the low-dose birth control pill which I was on for 5-6 years previously (aged 15/16-21). I have spent the majority of my reproductive life on some kind of hormonal birth control (for acne, then birth control) and have little memory of hormone-free periods, but can compare and contrast what I experienced.

PROS OF MIRENA

• Low maintenance birth control.
• Many studies have been conducted on it showing it was safe. I personally had worries about fertility, but this is with all birth controls because I really want children someday.
• Light spotting for a few months (daily for about 2 weeks, then on and off for about 2 or 3 months following that... not enough to leak through panties, but bad enough to stain them. I wore liners or light tampons if I cared to.) then no periods for 2+ years.
• Lost about 10 pounds gained on hormonal birth control.
• No mental side effects.

CONS OF MIRENA (after hormonal birth control pills)

• Skin got worse... not as bad as it was prior to birth control, but it was not as good as when on the pill.
• Migraines DUE TO WITHDRAWING FROM BIRTH CONTROL PILLS. This subsided within two weeks, though they were incredibly irritating for the time I was getting them. They generally hit around 8pm and could be managed with pain medicine and my vasodialating medication (a migraine-abortive medication) but still, were not ideal.
• Worries about fertility.
• Phantom pains because I knew that there was a 2" plastic rod in my vagina (I'm kinda paranoid).
• Checking for the strings, forgetting to check for the strings (no period to prompt poking around my vag), and not being able to find them when I remembered to check for them because they were short and I was bad at it. You're supposed to check monthly to make sure they're the same length.
• Only lasts 5 years.
• I had one cyst, about two years in. This is what ultimately worried me enough to get it removed (about 6 months after the fact, but I was shaken). I could feel something, somewhere, inside me for a few weeks. Then it burst. It was very painful for about 5 minutes, then I was cramp-y for a few days (i.e. no sit ups at the gym).

I guess in general, the first few weeks are not ideal. It feels worse than whatever you're used to (hormonal birth control, hormone-free, etc) because you're body is adjusting. The hormones are in a contained area and there were adjustments for me that you may not experience if you are not on hormonal birth control pills because my other body systems withdrew from the hormones. Overall I was very satisfied with it, but personally I dream of the day I have children (no judgements that you don't... kids are a choice and as someone who loves children I'd rather people who don't want kids not have them) and no matter how satisfied I am with what I have, I have to keep in mind my dreams. As someone who admits they don't get this feeling when they think of kids, it's like getting a degree. You may love your current job, but you dream of something bigger and better. To get there, you have to quit your job and go to school for a few years, which really sucks. It's time consuming, frustrating, and you want to give up. Then you finally graduate and get what you want. For me, Mirena was easy. I enjoyed my time with it. But I worry about the consequences of not getting off it due to my own dreams. I quit it, and got on a low-dose hormone I can stop at any time if I have regrets. Someday I will get off it for good, get pregnant, and have the baby of my dreams. But, for now, I'm a huge advocate of birth control and doing what you feel is right for your lifestyle and your body.