What Causes Pulsating Feeling In Groin Area And Upper Thigh?

For the last couple of days, I have been experiencing a vibrating / buzzing sensation in the right side of my groin and upper thighs (back of legs). I have no pain and it's just an annoyance at the moment. Just to give you an idea, imagine having your mobile phone in your pocket and you can feel it ringing(on the vibration setting) - that is a very similar 'feeling' that I have been experiencing. This feeling lasts for about 2 seconds with roughly a 5 second gap - this can go on for hours.