Objective This study was undertaken to examine the relationship betwe en labor abnormalities and shoulder dystocia in nulliparous women. Study design Nulliparo us women whose delivery was complicated by shoulder dysto...Objective This study was undertaken to examine the relationship betwe en labor abnormalities and shoulder dystocia in nulliparous women. Study design Nulliparo us women whose delivery was complicated by shoulder dystocia were studied and co mpared with a control group selected based on the best possible match for race, labor type (spontaneous or induced), and birth weight. The duration of first and second stage of labor, as well as the rates of labor progress, were calculated and compared between groups. Results During this 4-year study period, there wer e 8010 nulliparous singleton deliveries of which 65 (0.8%) were complicated by shoulder dystocia. Compared with controls, there was no difference in the rate o f cervical dilation in the active phase of the first stage of labor. In the shou lder dystocia group, more patients had a second stage of labor greater than 2 ho urs (22%vs 3%; P < .05) and had operative vaginal deliveries (26%vs 1.5%; P < .001). In shoulder dystocia cases with birth weight greater than 4000 g, 33%h ad a second stage of labor greater than 2 hours. Conclusion In our population, t he combination of fetal macrosomia, second stage of labor longer than 2 hours an d the use of operative vaginal delivery were associated with shoulder dystocia i n nulliparous women.展开更多
文摘Objective This study was undertaken to examine the relationship betwe en labor abnormalities and shoulder dystocia in nulliparous women. Study design Nulliparo us women whose delivery was complicated by shoulder dystocia were studied and co mpared with a control group selected based on the best possible match for race, labor type (spontaneous or induced), and birth weight. The duration of first and second stage of labor, as well as the rates of labor progress, were calculated and compared between groups. Results During this 4-year study period, there wer e 8010 nulliparous singleton deliveries of which 65 (0.8%) were complicated by shoulder dystocia. Compared with controls, there was no difference in the rate o f cervical dilation in the active phase of the first stage of labor. In the shou lder dystocia group, more patients had a second stage of labor greater than 2 ho urs (22%vs 3%; P < .05) and had operative vaginal deliveries (26%vs 1.5%; P < .001). In shoulder dystocia cases with birth weight greater than 4000 g, 33%h ad a second stage of labor greater than 2 hours. Conclusion In our population, t he combination of fetal macrosomia, second stage of labor longer than 2 hours an d the use of operative vaginal delivery were associated with shoulder dystocia i n nulliparous women.