Main Article Content
The correlational predictive design study aimed at investigating the influence of maternal age, pain during labor, duration of labor, administration of oxytocin, and blood loss during delivery on onset of lactogenesis II after delivery. The sample consisted of 175 primiparous mothers with vaginal delivery, delivering at Udonthani Hospital. The research instruments included the demographic characteristics questionnaire, the intrapartum record form, the labor pain record, the oxytocin administration record and the onset of lactogenesis II record. Data were analyzed using descriptive statistics, Chi-square analysis and logistic regression analysis.
The results showed that 62.3% of subjects had onset of lactogenesis II within six hours after delivery, and the median of onset of lactogenesis II was at 5 hour 36 minute after delivery. Duration of labor and administration of oxytocin were statistically significantly associated with onset of lactogenesis II within 6 hours after delivery (p < .05). Maternal age, pain during labor, duration of labor, administration of oxytocin, and blood loss during delivery together could statistically significantly predict onset of lactogenesis II within first six hours after delivery by 13.4% (Nagelkerke R2 = .134, p < .001). Only duration of labor, and administration of oxytocin were the key factors that could statistically significantly predict onset of lactogenesis II within first six hours after delivery (OR = 2.45, 95%CI: 1.21, 4.99, p =.013 ; OR = 2.34, 95%CI : 1.22, 4.51, p =.011, respectively).