Good question. The way it was explained to me, the twelve nidanas are all "made" from each other, they are all made from the same "stuff". It's like when there is water, the wave on the water and the foam on top of the wave - they all "grow" from one another. Similarly, consciousness is "made from" mental formations and feelings/perceptions "grow from" consciousness like foam on top of the wave.
So when the "new" consciousness is "born" - yes, it certainly "contains" (rides on top of, made of) the mental formations that led to it. Which is one of the ways karma perpetuates itself.
Mental formations (aka "tendencies") define the overall shape of the future action in broad brushstrokes, and then consciousness, feelings, perceptions, craving, etc. get more and more specific until the action itself, which leads to some results, that manifest as new experience on the next cycle and so on - this is how "tendencies" perpetuate themselves.
Tendencies (formations), consciousness, attraction/aversion, and karma grow from each other and carry the impulse of each other, so Samsara keeps rolling forward like this.