Abstract: Objective To study the dynamic changes in macronutrients and energy in human milk from mothers at early stage of premature infants, in order to explore the necessity of providing individualized nutrition support for premature infants. Methods A total of 140 human milk samples were collected from 70 women who delivered preterm infants from January to December 2017.Macronutrients and energy were tested using MIRJS human milk analyzer.The difference on the macronutrients and energy in different genders, maternal age, delivery mode, colostrum and transition milk group were analyzed and the changes were observed. Results 1) The protein level in colostrum from mother of premature was higher than that of transitional milk (P<0.01), while the fats, carbohydrates and energy were significantly lower in colostrum (P<0.05).2) The colostrum from mothers of premature infants with a gestational age of ≤30 weeks had significantly higher levels of protein than those of 30⁺¹-33⁺⁶ weeks and ≥34 weeks group (P<0.05).And the energy level in colostrum of ≤ 30 weeks group were significantly lower than that of 30⁺¹-33⁺⁶ weeks group (P<0.05), while the differences on fats and carbohydrates were not significant (P>0.05).3) The proteins, fats and energy levels in transition milk groups at different gestational age groups were not significantly different(P＞0.05).While the carbohydrates significantly increased with the older of gestational age [(6.28±0.57), (6.61±0.43), (6.36±0.81) g/100 ml), P=0.04].4) No significant difference was found on the content of macronutrients and energy in groups with different maternal childbearing age, delivery modes, infants′ gender and birth weight.5) The protein levels in breast milk were continuously declining while the fats, carbohydrates and energy levels were continuously increasing after linear fit.The tuning days of protein, fats, carbohydrates and energy levels were in the eleventh, ninth and fourteenth day after birth. Conclusions The levels of macronutrients and energy in milk from mothers of premature infants vary significantly between colostrum and transitional milk.Micronutrient and energy levels are not correlated with mothers′ childbearing age, delivery mode, infants′ gender and birth weight.Moreover, the proteins and ratio of protein/calorie are low in early stage of premature, and the compositions vary from person to person.Therefore, the protein content and calorie density of breast milk should be targeted to strengthen, and further study is warranted to explore the timing and composition of premature infants′ human milk additives.

Key words: premature infants, colostrum, transition milk, components of human milk

摘要： 目的 分析早产儿生后早期母乳各大营养成分变化的特点,初步探讨提供早产儿个性化营养支持的必要性。 方法 收集2017年1-12月在南京医科大学附属常州妇幼保健院分娩产妇70人的母乳140份,用MIRIS母乳分析仪检测母乳中宏量营养成分及能量,比较不同早产儿性别、乳母年龄和不同分娩方式初乳和过渡乳母乳营养成分的差异及随着出生天数所发生的变化。 结果 1)早产母乳中初乳蛋白质含量大于过渡乳(P<0.01);初乳的脂肪、碳水化合物和能量低于过渡乳(P<0.05)。2)≤ 30周早产初乳蛋白质含量最高,与30⁺¹~33⁺⁶周组和≥34周组比较差异有统计学意义(P<0.05);≤ 30周早产初乳能量显著低于30⁺¹~33⁺⁶周(P<0.05),而脂肪、碳水化合物差异无统计学意义(P>0.05);3)不同胎龄的三组过渡乳中蛋白质、脂肪、能量差异均无统计学意义(P>0.05);碳水化合物分别为(6.28±0.57)、(6.61±0.43)、(6.36±0.81) g/100 ml,随着孕周增加而增加,差异有统计学意义(P＝0.04)。4)母乳营养成分含量在孕母生育年龄、分娩方式、婴儿性别、出生体重方面差异均无统计学意义。5)线性拟合后发现母乳中蛋白质在生后持续下降,其折点天数在第11天,同时,线性拟合发现脂肪、糖类和能量含量呈增长趋势,脂肪变化的折点在出生后第9天,而糖类以及能量在出生14 d内呈近似线性增长关系。结论 早产初乳、过渡乳营养成分差异显著,母乳营养成分含量与孕母生育年龄、分娩方式、婴儿性别、出生体重无相关性。早产儿早期蛋白质累计缺乏以及蛋白质/热卡比例较低,且早产母亲母乳成分的个体差异较大,应该对母乳中蛋白质含量和热卡密度进行“目标性”强化,对母乳添加剂添加需进一步研究。

关键词: 早产儿, 初乳, 过渡乳, 母乳成分