Abstract

Obstructed labour, also known as labour dystocia, is when, even though the uterus is contracting normally, the baby does not exit the pelvis during childbirth due to being physically blocked. 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 obstetrical fistula. Obstructed labour is said to result in prolonged labour, when the active phase of labour is longer than twelve 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. 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.

The treatment of obstructed labour may require cesarean section or vacuum extraction with possible surgical opening of the symphysis pubis. Other measures include: keeping the women hydrated and antibiotics if the membranes have been ruptured for more than 18 hours. In Africa and Asia obstructed labor affects between two and five percent of deliveries. In 2015 about 6.5 million cases of obstructed labour or uterine rupture occurred. This resulted in 23,000 maternal deaths down from 29,000 deaths in 1990 (about 8% of all deaths related to pregnancy). It is also one of the leading causes of stillbirth. Most deaths due to this condition occur in the developing world.

Cause

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. while problems with the birth canal include a narrow vagina and perineum which may be due to female genital mutilation or tumors.

Diagnosis

Obstructed labour may be diagnosed based on physical examination.

Treatment

The treatment of obstructed labour may require cesarean section or vacuum extraction with possible surgical opening of the symphysis pubis. Other measures include: keeping the women hydrated and antibiotics if the membranes have been ruptured for more than 18 hours.

Prognosis

If cesarean section is obtained in a timely manner, prognosis is good. Prolonged obstructed labour can lead to stillbirth, obstetric fistula, and maternal death.

Epidemiology

In 2013 it resulted in 19,000 maternal deaths down from 29,000 deaths in 1990.

Etymology

The word dystocia means difficult labour. Its antonym is eutocia () or easy labour.

Other terms for obstructed labour include: difficult labour, abnormal labour, difficult childbirth, abnormal childbirth, and dysfunctional labour.

Other animals

The term can also be used in the context of various animals. Dystocia pertaining to birds and reptiles is also called egg binding.

In part due to extensive selective breeding, miniature horse mares experience dystocias more frequently than other breeds.