A descriptive analysis of involuntary bearing-down efforts during the expulsive phase of labor.

A series of descriptive studies was carried out to characterize maternal respiration, type of bearing-down efforts, vocalization, and behavior; describe the obstetric conditions and intrauterine pressure associated with the bearing-down reflex; and describe the duration of second stage, fetal heart rate, and neonatal outcomes when women bear down spontaneously. Thirty-one healthy nulliparous women who had received no formal childbirth education were neither directed nor instructed to bear down with contractions. The women were supported in their involuntary bearing-down efforts throughout the second stage of their labors while the above features of their labor were recorded. The findings suggest that labor progress is adequate and fetal outcome is good when the management of the expulsion phase of labor encourages maternal pushing that is complementary with the involuntary bearing-down reflex rather than sustained breath-holding. These findings support the necessity for further research regarding the bearing-down techniques used during labor.