birth control
"I got a Paragard at 24 and have never been pregnant. The insertion was not too painful, having the speculum inserted for about 3 minutes was uncomfortable and it just felt like period cramps the rest of the day. The first time I was sexually active a few days after insertion it hurt a bit but that was it. No pain after that but had pretty continual bleeding for 3 months. The bleeding was very light, I put a diva cup in all day and didn't worry about it, didn't even need it at night. 
Only once at about 3 moths in after fairly rough sex I had a stabbing pain in the lower right side of my abdomen. Took an Advil which made it go away. Went to the doctor and the iud was in the proper place. Doctor said it could have been ovulation."