Sex on period with implant?

Paris.
Okay so I have the implant, and I've been toying with the idea of shower sex whilst on my period as it would be less messy.
Basically what I'm asking is, i know it's still possible to get pregnant whilst on your period - but I am on the implant, so is there still a chance? I wouldn't be using a condom because of the implant and shower factor.
(Sorry it seems so basic but I just don't know)
Anything would be appreciated!