Obstructed labour, also known as labour dystocia, is the baby not exiting the pelvis because it is physically blocked during childbirth although the uterus contracts normally. Complications for the baby include not getting enough oxygen which may result in death. It increases the risk of the mother getting an infection, having uterine rupture, or having post-partum bleeding. Long-term complications for the mother include obstetric fistula. Obstructed labour is said to result in prolonged labour, when the active phase of labour is longer than 12 hours.
The main causes of obstructed labour include a large or abnormally positioned baby, a small pelvis, and problems with the birth canal. Abnormal positioning includes shoulder dystocia where the anterior shoulder does not pass easily below the pubic bone. Risk factors for a small pelvis include malnutrition and a lack of exposure to sunlight causing vitamin D deficiency. It is also more common in adolescence as the pelvis may not have finished growing by the time they give birth. Problems with the birth canal include a narrow vagina and perineum which may be due to female genital mutilation or tumors. A partograph is often used to track labour progression and diagnose problems. This combined with physical examination may identify obstructed labour.