The Bearina is a conceptual open-source, 3D printable IUD that uses a one-cent coin to as the chemical reactant by Open Design advocate Ronen Kadushin..  

The Bearina IUD is a political product. It demonstrates the disruptive potential of 3D printed Open Designs to give free and global access to essential products, and circumvent industries (such as the Pharma industry) that aggressively defend their intellectual property to control the price and availability of their products. As an Open Design, the Bearina IUD promotes collaborative development and free sharing of knowledge. Further developed by a networked community or in partnership with a forward looking pharma company, It is always available for experimenting with and improving, and could evolve into a functional IUD.

The Bearina, with its bear head image, is visually friendly, to appeal, so to speak, to younger women. It is a conceptual product, a design fiction, and absolutely should not be used as an IUD. Nevertheless, it is designed according to dimensions, materials and shapes commonly found in IUDs.

As well as being 3D printable via Shapeways you can also download the file from Ronen's site if you want to change the dimensions for another coin. Hey, you might even wear it as a pendant or earrings to show your affinity with the cause.

Disclaimer: Shapeways in no way endorses the use of this device for real, conceptual use only