[Current aspects of engagement dystocia].

It seems likely, in view of the large number of caesarean operations that are now being carried out and that too have complications, that the mechanism of obstetric procedures will sooner or later become of interest again to obstetricians. This study looks at a consecutive series of cases where dystocia in the upper part of the pelvis occurred and tries by analysing different obstetrical parameters to work out the best time for carrying out different obstetrical manoeuvres. It is possible to come to two conclusions, so long as both the mother and the fetus are watched carefully during the labour: the trial of delivery of the fetal head using the obstetric ventouse will bring about a significant reduction in the numbers of caesarean operations. it is always rewarding to be patient and it does not seem sensible to intervene too quickly. Two important results come from this approach: mechanical dystocia has practically disappeared, as it now only occurs in about 1% of labours. on the other hand, particularly in primiparous women, dystocia in the upper straight of the pelvis is quite common.