"effectiveness.. well i was the 1% of the population to get pregnant from the iud. i ended up in the er because of moderate to severe abdominal pain, bloating, and bleeding. i had weird symptoms and i didn&#039;t think it was time for my period so i called my gyno and she said i was probably fine but just take a pregnancy test (i was concerned my iud shifted). the pregnancy test was positive so we knew something was very wrong so ended up in er with an ectopic pregnancy and a huge ovarian cyst. i had emergency surgery to remove my fallopian tube. i had the iud for 5 months and it was not a pleasant experience, i had cramping that was severe even months after i got it put in, to the point i was hurled over. but it may have been the cyst growing."