Anonymous #2 4w

R&D is expensive and drug makers are motivated to launch medications so they can start earning back the costs. A three year lifespan was deemed good enough, so they stopped the studies and went for FDA approval. Since then, longer studies have been conducted showing continued effectiveness through year 5 and they were able to extend official guidance. This is common with LARCs; Mirena was originally approved for 5 and was extended to 8!

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