Hey there, Rachel. And thanks for coming here to work with our Twitter policies. This actually is a pretty short answer, but we have to hold a line with answering questions there or else it would be mania.
Ultimately, whether we're talking implant, IUD or Nuvaring, they all basically do this the same way. They're made of materials -- kinds of plastics -- which contain the medication, and then slowly release them over time. Which specific kind of plastic is chosen for any kind of delivery device like this (contraception or other medications) apparently has to do with how fast or slowly the medication is intended to be delivered.
Does that make sense and answer what you were asking?