Symphysiotomy for feto-pelvic disproportion

Symphysiotomy is an operation to enlarge the capacity of the mother’s pelvis by partially cutting the fibres joining the pubic bones at the front of the pelvis. Usually, when the baby is too big to pass through the pelvis, a caesarean section is performed. If caesarean section is not available, or the mother is too ill for, or refuses, caesarean section or if there is insufficient time to perform caesarean section (for example when the baby’s body has been born feet first, and the head is stuck), symphysiotomy may be performed. Local anaesthetic solution is injected to numb the area, then a small cut is made in the skin with a scalpel, and most of the fibres of the symphysis are cut. As the baby is born, the symphysis separates just enough to allow the baby through. Large observational studies have shown that symphysiotomy is extremely safe with respect to life-threatening complications, but rarely may result in pelvic instability. For this reason, and because the operation is viewed as a ‘second-class’ operation, it is seldom performed today. Health professionals fear censure should they perform a symphysiotomy which leads to complications. Proponents argue that many deaths of mothers and babies from obstructed labour in parts of the world without caesarean section facilities could be prevented if symphysiotomy was used. This review found no randomized trials evaluating symphysiotomy.

Authors' conclusions: 

Because of controversy surrounding the use of symphysiotomy, and the possibility that it may be a life-saving procedure in certain circumstances, professional and global bodies should provide guidelines for the use (or non-use) of symphysiotomy based on the best available evidence (currently evidence from observational studies). Research is needed to provide robust evidence of the effectiveness and safety of symphysiotomy compared with no symphysiotomy or comparisons of alternative symphysiotomy techniques in clinical situations in which caesarean section is not available; and compared with caesarean section in clinical situations in which the relative risks and benefits are uncertain (for example in women at very high risk of complications from caesarean section).

Read the full abstract...

Symphysiotomy is an operation in which the fibres of the pubic symphysis are partially divided to allow separation of the joint and thus enlargement of the pelvic dimensions during childbirth. It is performed with local analgesia and does not require an operating theatre nor advanced surgical skills. It may be a lifesaving procedure for the mother or the baby, or both, in several clinical situations. These include: failure to progress in labour when caesarean section is unavailable, unsafe or declined by the mother; and obstructed birth of the aftercoming head of a breech presenting baby. Criticism of the operation because of complications, particularly pelvic instability, and as being a 'second best' option has resulted in its decline or disappearance from use in many countries. Several large observational studies have reported high rates of success, low rates of complications and very low mortality rates.


To determine, from the best available evidence, the effectiveness and safety of symphysiotomy versus alternative options for obstructed labour in various clinical situations.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (7 July 2012).

Selection criteria: 

Randomized trials comparing symphysiotomy with alternative management, or alternative techniques of symphysiotomy, for obstructed labour or obstructed aftercoming head during breech birth.

Data collection and analysis: 

Planned methods included evaluation of studies against objective quality criteria for inclusion, extraction of data, and analysis of data using risk ratios or mean differences with 95% confidence intervals. The primary outcomes were maternal death or severe morbidity, and perinatal death or severe morbidity.

Main results: 

We found no randomized trials of symphysiotomy.