This document discusses several potential complications of labor and delivery, including: 1) Preterm labor or premature labor, which occurs more than three weeks before the due date, and can result in premature birth. 2) Long or prolonged labor, which is determined by labor stage and cervical changes, and may occur after 20 hours of regular contractions. Causes include a large baby, abnormal baby position, or a small birth canal. 3) Obstetric trauma during vaginal delivery without instruments, which includes 4th degree perineal lacerations and injuries to the cervix, vagina, bladder or urethra.