Background. Pushing in the second stage of labor can be forced or follow the spontaneous urge to bear down. Recent studies have shown that spontaneous pushing results in a longer second stage, fewer CTG changes, higher arterial pH and less damage to the birth canal. Method. Randomized trial of spontaneous vs. forced pushing in 350 primiparous women. Results. There was no difference between the randomized groups in duration of second stage of labor, umbilical arterial pH or damage to the birth canal. Of the women allotted to spontaneous pushing, 65.6% used the closed glottis technique for more than half the expulsive phase. When dividing the women into two groups according to the actual pushing technique used most, open or closed glottis, it turned out that women who used the open glottis technique had a shorter second stage of labor and gave birth to infants with lower birth weight.
Conclusion. Recommending of spontaneous bearing down during the expulsive phase of labor did not result in a significant difference in duration of the second stage of labor, fetal arterial pH or less damage to the birth canal. Women who chose the open glottis technique had a shorter expulsive phase and gave birth to smaller infants than those who used the closed glottis technique.