Calling Llama Experts!

My family has been breeding llamas for a few years now. We choose all of our breeders for their height, health, how flat their backs are, and the classic coat. Last year we bred our females in May for an April birth. The problem we are now having is the decision on whether or not to shear them. We usually shear every other year in the spring- the same time the crias would be due. My question is: do you think this would put too much stress on the girls and cause them to go into early labor? or will they be alright.
Please let me know what you think
thanks