Ah, condoms — the perfect fit for bananas and penises. When used correctly, condoms can be a highly effective way to prevent pregnancy and sexually transmitted infections. And part of using them correctly includes only using condoms once, and then throwing them away — not washing them and reusing them.
Sure, we're all about reducing, reusing and recycling when appropriate, but when an unplanned pregnancy or STI is at stake, it's definitely not an appropriate time to be reusing a condom. This has apparently become such an issue that the Centers for Disease Control thought it was necessary to tweet about it.
There are several reasons condoms should not be reused, including the fact that condoms were not designed to be washed and may not come out clean (or even tear-free) post-wash.
On top of that, part of effective condom usage is rolling it onto the penis, which is not possible if a condom has already been used. If you need more specifics about how to put a condom on (including visuals), the CDC's website has a step-by-step guide.
And yes, condoms can get expensive, but the good news is that there are places and organizations that give them away for free. (We even put this handy list together for you.) Though we support efforts to be thrifty and environmentally friendly, this isn't the place to do it.
So, if you or a partner ever finds yourself in a situation where you're thinking of washing and reusing a condom, remember this PSA from the CDC and just don't do it (until you get your hands on a new unopened condom).