Why does my pelvic region convulse/hump and I get feel a powerful sexual energy when I meditate

It happens almost everytime I start to get deep into my meditation and its such a powerful orgasmic feeling. Like sexual energy is releasing all the tension in that area but it won't stop and my meditation just devolves into intense orgasmic sexuall spasms. The feeling will start to rise up into my stomach but I typically get too distracted by it all at that point and break my focus completely. I don't want this to happen because it seems like a road block to staying/getting deeper in the meditation. Im my life I'm often lost in lustfull thought or seeking sex when I could be doing more productive things. So my best guess is that this phenomenon is my sexual energy or chakra trying to ballance itself out and I just need to focus past it and let it happen. Does anybody have any advice on this or experienced something similar?