What Causes A Tingling Sensation Between Spine And Shoulder Blade?

At the onset of orgasm I get an instantaneous very sharp tingling sensation, like being pricked with a needle, between my spine and left shoulder blade. This happens no matter what position I am in and every time. I have only noticed this the last couple of months. I have no injuries or diseases that I am aware of...fairly healthy I believe. I am 47, peri-menopausal, 5 7 and 195lbs.