[Length of pushing efforts: pushing is not playing. Reply to the article of C. Le Ray and F. Audibert]. / Durée des efforts expulsifs : pousser n'est pas jouer. Réponse à l'article de C. Le Ray et F. Audibert.

ABSTRACT

The aim of this work is to answer constructively to C. Le Ray and F. Audibert who were surprised that the French guidelines recommended an assisted delivery after 30 min pushing, even if the fetal heart rate is reassuring. We first resumed the definition of "second stage of labor", this word including the first phase with no pushing efforts and the second phase with active pushing of the mother. With that definition, the length of the second stage is around 60 min for the primipara and 20 min for the multipara, this length being modified by the use of peridural. We then specified the physiological mechanisms influencing the acidobasic equilibrium during the pushing time. Those mechanisms are difficult to consider because foetal heart rate monitoring is often "lost" during that phase. Altogether, these factors bring incertitude about progressive foetal acidosis and incapacity to diagnose it. Finally, the literature analysis teaches us that increasing the second stage of labor (inactive plus active phases) during the normal pregnancy seems to be at low risk for the foetus within the primiparas, but display a risk for the mother and so might be limited. Comparing the delayed pushing with the immediate pushing only lead us to conclude that delayed pushing is dangerous, as is prolonged second stage. In conclusion, we think that prolonging the second stage of labor is possible but must be by increasing the inactive first phase of the second stage, especially as long as we will not get a noninvasive and reliable method allowing assessing the well-being of the foetus.