It's impossible to predict what kind of labor you will have, but it can be reassuring to plan for various scenarios. One possibility is back labor, which can be caused by the back of your baby's head pressing into your spine. Back labor can be painful, as the baby's position can cause contractions to be felt in the back as well as the womb.

"The pain of back labor is continually present, but worsens with each uterine contraction," explained Jessica Madden, M.D., a pediatrician, neonatologist and medical director at Aeroflow Breastpumps. "Back labor can be differentiated from regular labor because during back labor, women will not get any relief from pain in between their contractions."

While back labor isn't harmful to the baby, it can be more difficult for the birthing parent. I had back labor with my son and experienced painful spasms in my back, in addition to my regular contractions.