How does the Bhavanga State relate to the Jhanas?

When we sit down and practice samadhi we would naturally want to enter absorbtion.But what if by practicing samatha we manage to calm and refine all the five senses,to the point where all five senses dissapear. What's left would only be the **mind sense** with **no outer stimuli from the five senses**. If this happens then won't the mind grasp the Bhavanga State? So my question is How does the Bhavanga State relate to the Jhanas?Are you suppose to go through one before entering the Jhanas.Or are you suppose to avoid lapsing into one in the first place.