Parity, total second stage of labor duration, duration of second labor stage beyond one hour, and perinea wound pain were the most significant predictors of delayed lactation onset.

• (3)产次、第二产程时间、第二产程时间大于一小时、第一到第三天会阴伤口疼痛分数，是延迟首次泌乳时间的重要预测因子。