Undiagnosed breech

To assess the proportion of breech presentations diagnosed in labour and to compare their outcomes with those diagnosed prior to the onset of labour.

Retrospective casenote review.

Mill Road Maternity Hospital, a teaching hospital in central Liverpool.

Three hundred and five singleton breech presentations delivered in the hospital between January 1988 and July 1991; 226 cases prior to the onset of labour and 79 cases diagnosed for the first time in labour.

Rates of vaginal delivery and caesarean section, birthweight, short term morbidity as assessed by trauma, signs of cerebral irritation and admission to the newborn intensive care unit (NBICU), and Apgar scores.

Breech presentations diagnosed for the first time in labour were more likely to deliver vaginally than those assessed and allowed to go into labour (odds ratio 1:68 95% CI 1.0-3.0). This difference was not due to demographic variables or differences in birthweight. There was no short term morbidity attributable to vaginal breech delivery.

A significant number of breech presentations are not detected until labour despite rigorous antenatal surveillance. Our results show that undiagnosed breeches may not be important as they are more likely to deliver vaginally, with no excess morbidity or mortality, compared to diagnosed breeches in labour, carefully assessed for vaginal delivery. There are, therefore, no grounds for delivering all undiagnosed breeches by caesarean section.