Nanotechnology has finally made its way into the bedroom, with a new type of condom that uses nanoscale silver foam.

The condom for women, made by a Chinese company called Blue Cross, uses "introduced American scientific research achievement and advanced technology of nanometer-silver and physical foaming".

The "double-barrier technology, white and fine foam" is sprayed internally "to bring the effects of integration of conception control, antibiosis and lubrication into a whole." No pun intended, we're sure.

Every condom has a silver lining

The "formulated condom concentrate" contains polyvinyl alcohol resin and nano-silver, the antibacterial material that is increasingly found in air conditioners, washing machines and baby bottles.

However, there has been concern that nano-scale silver particles may get into the water supply and potentially disrupt benign bacteria at water treatment plants.

The Blue Cross website is silent on whether the foam condom has been approved by any recognised consumer safety or reproductive health organisations, but you shouldn't worry too much about that, as there's no indication where you can buy the contraceptive anyway.

If the idea of a foam condom isn't dissuasive enough, its mode of operation might tip the balance: it needs to be used no more than five minutes before sex. And then again immediately afterwards.