易混淆的单词： Nulliparous

Labor analgesia and cesarean delivery : an individual patient meta-analysis of nulliparous women .

分娩镇痛和剖宫产：初产妇个体病人的meta-分析。

Inefficient uterine action is the most common cause of dystocia in the nulliparous gravida , especially early in labor .

宫缩乏力是初产妇难产最常见原因，尤其是第一产程。

Second-stage labor duration in nulliparous women : relationship to maternal and perinatal outcomes .

未产妇的第二产程持续时间：与产妇及新生儿围生期结局的相关性。