Gardner Hazel, Kent Jacqueline C, Prime Danielle K, Lai Ching-Tat, Hartmann Peter E, Geddes Donna T
School of Chemistry and Biochemistry, M310, The University of Western Australia, Crawley, Western Australia, 6009.
Medela AG, Lättichstrasse 4b, Baar, 6341, Switzerland.
Am J Hum Biol. 2017 May 6;29(3). doi: 10.1002/ajhb.22960. Epub 2017 Jan 17.
Milk ejection is a critical physiological process for successful lactation in humans and without it little milk can be removed. Individual milk ejection patterns have been shown to remain consistent between breasts at different lactation stages and using different vacuum patterns with an electric breast pump. Little is known about the milk ejection characteristics during the second lactation period in the same mother. The objective of this study was to examine milk ejection characteristics in the same woman over two lactations.
One mother took part in two pumping studies during consecutive lactations. One pumping study examined milk ejection characteristics during simultaneous breast expression during the first lactation. The second pumping study (second lactation) used two different pumping patterns. Three distinct milk ejections were measured during each pumping session.
Measurements of milk flow were used to compare the duration and time taken to reach the peak of each milk ejection for two pumping sessions from each of the lactations. There were no significant differences in milk ejection characteristics between breasts, using different pumping patterns, or between lactations in this mother (P > .05).
Milk ejection appears to be a physiological response that is consistent across consecutive lactations within the same mother. This suggests that milk ejection characteristics are established during or prior to the first lactation. The infant appears to have little influence on the milk ejection characteristics of the mother.
乳汁排出是人类成功泌乳的关键生理过程，没有它则几乎无法排出乳汁。研究表明，在不同泌乳阶段以及使用电动吸奶器的不同真空模式时，个体的乳汁排出模式在两侧乳房之间保持一致。对于同一母亲第二次泌乳期间的乳汁排出特征，人们了解甚少。本研究的目的是检查同一女性在两次泌乳过程中的乳汁排出特征。
一名母亲在连续两次泌乳期间参与了两项吸乳研究。一项吸乳研究在第一次泌乳期间同步双侧乳房吸乳时检查乳汁排出特征。第二项吸乳研究（第二次泌乳）采用两种不同的吸乳模式。每次吸乳过程中测量三次不同的乳汁排出情况。
使用乳汁流量测量结果来比较每次泌乳的两次吸乳过程中每次乳汁排出的持续时间和达到峰值所需的时间。在该母亲中，两侧乳房之间、使用不同吸乳模式时以及两次泌乳之间的乳汁排出特征均无显著差异（P>0.05）。
乳汁排出似乎是一种生理反应，在同一母亲的连续泌乳过程中保持一致。这表明乳汁排出特征在第一次泌乳期间或之前就已确立。婴儿似乎对母亲的乳汁排出特征影响很小。
