"i had implanon inserted in september of 2009.  so far, i have been very happy.  i had frequent periods (every 2-3 weeks for only a couple of days) for the first 3 months.  since then i haven&#039;t had my period and not even symptoms of it.  that part has definitely been great.  i did feel it made me pretty moody for the first 2-3 months but has tapered off.  i haven&#039;t experienced any weight gain as some have reported.  i have a pretty high activity level (running about 20 miles per week) and have been eating as i normally do.  the most major side effect i have is a decrease in sex drive which is a pretty big downside but considering i haven&#039;t experienced other side effects i rate this form of birth control highly."