Think of it this way. As a man, you have hormones such as testosterone surging through your body. Say, someone was to take away that testosterone or maybe even give you more. If you had too little testosterone, you would become less prone to male urges,  and if you had too much testosterone, you would become increasingly aggressive. Take a woman on too much progesterone. She is in a state of PMS 24/7 and she no longer has the cyclic hormones that will take the edge off to "normalize" her moods. Stress builds up in her body, which effects her back, her joints, and her sanity. She does still ovulate, but no has no uterine lining for the egg to attach itself to if it becomes fertilized, therefore, is re-absorbed into the system. (This is why she has no period by the way).

Our bodies go through a natural cycle, and that cycle is delicate. The only time this cycle is interrupted is during menopause. At that time, the eggs are getting old, and the body no longer needs to produce as much of the hormones needed for pregnancy, therefore, shutting down for the evening of our lives. I believe that interrupting our natural cycle can lead to health problems, such as those seen in menopausal women. Hormones derived birth control is not for everyone, and these women on this forum are the cases in point. I find the symptoms from each of these women to be too similar to be a mere coincidence; therefore, the mirena and lack of menstruation can't be good for our bodies. Like I said, everyone reacts differently to hormones. I just happen to be someone who can't take hormones without consequence. Read some of the symptoms women have had, and judge for yourself. Believe me, the thought at first thrilled me, and the act of not having a period for over 3 years was great! However, I was unaware that all of my back problems and other symptoms could have stemmed from the mirena. I had no idea until the first day I stumbled onto this forum. I never put it all together until I started reading what sounded literally like something I had written myself. It made me cry to think that such a seemingly simple and harmless device could cause such problems. I lost my marriage, my friends, and almost my sanity in the process before I realized the mirena was the culprit. I have a long way to go to getting back to my old self, but I am definitely headed the right direction. No hormones for me. Think it over good and long before you decide to have one of these devices inserted into her uterus. Take a look at the post from the man who is hanging onto his marriage by a thread. He is knee deep in the symptoms, so ask yourself if you want that to be you and your wife.