Influencing factors of milk volume in mothers of preterm infants in neonatal intensive care unit during maternal separation / 中华围产医学杂志

ABSTRACT

Objective:To analyze the factors influencing breast milk volume in mothers of preterm infants during the period of maternal separation.Methods:This study retrospectively analyzed the data from lactation diaries of mothers of preterm infants ( n=371) in neonatal intensive care unit from the first Affiliated Hospital of Zhengzhou University from January 2017 to August 2021. According to whether the milk production reached 800 ml/d or not within two weeks after delivery, these women were divided into the reached group ( n=289) or unreached group ( n=82). Two independent sample t-test and Chi-square test were used for univariate analysis, and logistic regression was used to analyze the influencing factors. Results:Mothers who achieved the target milk volume accounted for 77.9% (289/371). There were no statistically significant differences in the ratio of milk production ≥50 ml between breasts or between two adjacent breastfeeding sessions (both P>0.05), while there were statistically significant differences in the maternal education background[high school education or below16.3% (47/289) vs 41.5% (34/82); junior college or above83.7% (242/289) vs 58.5% (48/82); χ2=23.77], type of breast pump [diaphragm breast pump34.9% (101/289) vs 51.2% (42/82); piston pump 65.1% (188/289) vs 48.8% (40/82); χ2=7.14], pre-pregnancy body mass index [<18.5 kg/m 2 3.5% (10/289) vs 4.9% (4/82);≥18.5～<24.0 kg/m 2 90.7% (262/289) vs 61.0% (50/82); ≥24.0 kg/m 2 5.9% (17/289) vs 34.1% (28/82); χ2=40.89], and the initiation of lactation instruction [within 7 d after delivery 77.2% (223/289) vs 45.1% (37/82);at 7-14 d after delivery 22.8%(66/289) vs 54.9%(45/82); χ2=31.28] between the reached and unreached group (all P<0.05). Logistic regression analysis showed that high school education or below ( OR=4.279, 95% CI 2.253-8.126, P<0.001), diaphragm breast pump ( OR=2.352, 95% CI 1.309-4.226, P=0.004), pre-pregnancy body mass index ≥24.0 kg/m 2 ( OR=9.352, 95% CI 4.389-19.928, P<0.001), and seeking lactation consultation at 7-14 d after delivery ( OR=3.654, 95% CI 2.043-6.535, P<0.001) were risk factors for not achieving the target milk volume. Conclusions:Instruction on breastfeeding for less-educated mothers of preterm infants should be strengthened. Using piston breast pump, maintaining pre-pregnancy body mass index within the normal range, and receiving lactation instruction as early as possible will contribute to achieving the target milk volume.