Gestational diabetes is a risk factor because the fetal shoulders and abdomen are dispropoionately bigger than the head, therefore the head may pass through with no problems, yet it is quite difficult to deliver the anterior shoulder since it is lodged behind the maternal symphysis pubis. The McRobes maneuver and application of suprapubic pressure are two techniques that attempt to relieve the impaction of the anterior shoulder. Unlike gestational diabetes, the complication with hydrocephalus is that the fetal head is greater than the body. The head itself may have a difficult time passing through the pelvis, but if it does pass, the shoulders would have no problem passing through since their width would be smaller than the width of the fetal head. The pre-mature fetus typically has a well-propoioned body, but is overall smaller in size than the average-sized baby. No pa of a premature fetus body should typically get impacted anywhere along the bih canal. With precipitous labor, there is a decreased chance that a shoulder dystocia will occur, whereas a prolonged second stage of labor should raise suspicion that a dystocia is present.