"i received the nexplanon implant in september 2013, after my gyno was unable to insert the mirena (i have never had children, so that made it difficult). i have always had irregular periods (usually once every 2 months on average), and my gyno told me that i will probably not get my period very often at all on the nexplanon. unfortunately, the opposite has been true. i&#039;m bleeding probably 25/30 days of the month, and it&#039;s preceded by a dark brown &quot;goo&quot; that was never present before. in the first few months, i had mood swings (irritability, anger, sadness), but that passed. i am getting it removed soon, but i gave it a 5/10 rating because it did its job -- i have not become pregnant. it did not work perfectly for me, but it may work for you."