Status and influencing factors of delayed onset of lactogenesis Ⅱ in mothers of preterm infants / 中华围产医学杂志

ABSTRACT

Objective:To investigate the incidence of delayed onset of lactogenesis Ⅱ (DOL Ⅱ) in mothers of preterm infants and its influencing factors.Methods:This retrospective cohort study involved women who delivered prematurely at the Department of Obstetrics of the First Affiliated Hospital of Zhengzhou University from September 2021 to March 2022. Demographic and perinatal data of the subjects were collected. According to lactation outcome on the third day after delivery, these women were divided into DOL Ⅱ and non-DOL Ⅱ groups. The two groups' differences in general conditions were compared, and the potential factors influencing DOL Ⅱ were also analyzed. Chi-square test, two independent samples t-test, Mann-Whitney U test, and logistic regression analysis were used for statistical analysis. Results:There were 286 mothers of premature infants enrolled in this study, and 73 (25.5%) of them experienced DOL Ⅱ. The other 213 cases without DOL Ⅱwere included as the non-DOL Ⅱ group. Univariate analysis showed significant differences between the DOL Ⅱ and non-DOL Ⅱ groups in the following aspects: the proportion of women with adverse pregnancy history [28.8% (21/73) vs 41.8% (89/213), χ2=3.89], the proportion of primiparas [60.3% (44/73) vs 38.0% (81/213), χ2=10.93], the incidence of hypertensive disorders of pregnancy [35.6% (26/73) vs 16.4% (35/213), χ2=11.92], the time to initiate breastfeeding after birth[5.0 h (3.0-7.0 h) vs 4.0 h (2.0-5.0 h), Z=－4.27], and the frequency of breastfeeding or pumping within 48 h after delivery [7.0 times (6.0-9.0 times) vs 9.0 times (7.0-11.0 times), Z=－3.62] (all P<0.05). Multivariate logistic regression showed that primipara ( OR=2.720, 95% CI: 1.485-4.982), hypertensive disorders of pregnancy ( OR=3.178, 95% CI: 1.609-6.274), the time to initiate breastfeeding ( OR=1.394, 95% CI: 1.211-1.604) and the frequency of breastfeeding/pumping within 48 h after delivery ( OR=0.861, 95% CI: 0.772-0.962) were independent influencing factors for DOL Ⅱ (all P<0.05). Conclusions:?The factors that influence the occurrence of DOL Ⅱ in preterm mothers are primipara hypertensive disorders of pregnancy, breastfeeding initiation time after delivery, and the frequency of breastfeeding or pumping within 48 h postpartum.