Reyes Sarah M, Allen Dainelle L, Williams Janet E, McGuire Mark A, McGuire Michelle K, Rasmussen Kathleen M, Hay Anthony G
Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA.
Rev Bioscience, LLC, Boise, ID, USA.
J Transl Med. 2025 Aug 21;23(1):947. doi: 10.1186/s12967-025-06967-5.
Human milk (HM) harbors a unique microbiome that contributes to the development of the infant gastrointestinal microbiome and influences long-term health outcomes. While pumping and bottle-feeding HM are increasingly common, doing so may introduce exogenous bacteria, altering this microbial community. The extent to which real-world pumping and hygiene practices alter the HM microbial community remains inadequately characterized.
We conducted a secondary analysis of 104 paired milk samples from 52 healthy women to investigate the associations between at-home pump hygiene practices and the HM microbiota. We compared samples expressed with personal equipment, allowing women to follow their typical practices, noting variations in breast pump types (closed- vs. open-systems), pre-pumping handwashing, and collection kit cleaning practices (OWN). Milk was also expressed with hospital-grade pump with new, commercially sterilized equipment kits under study-controlled conditions (STER) to serve as a control representing each woman's own unaltered milk microbiota. Microbiota composition was characterized using aerobic culture and 16S rRNA gene sequencing.
Among OWN milk samples, personal breast pump type had little impact on the HM microbiota. Pre-pumping handwashing, practiced by only 22% of participants, was associated with lower bacterial counts. Compared to samples expressed with handwashed kits, those expressed using home-sterilized kits yielded fewer total and gram-negative bacterial counts, and lower relative abundances of Proteobacteria. The microbiota of OWN milk samples expressed with home-sterilized kits more closely resembled STER samples even in the absence of pre-pumping handwashing (R = 0.36; P < 0.001).
At-home hygiene practices, particularly collection kit cleaning methods, substantially influence the HM microbiota. Home sterilization of collection kits may minimize changes to the HM microbiota during expression. These findings support evidence-based recommendations for hygienic pumping practices and underscore the need for further research on the health implications (if any) of pumping-dependent variations in the HM microbiota on infant health.
人乳中含有独特的微生物群，有助于婴儿胃肠道微生物群的发育，并影响长期健康结果。虽然吸乳和奶瓶喂养人乳越来越普遍，但这样做可能会引入外源细菌，改变这种微生物群落。现实世界中的吸乳和卫生习惯改变人乳微生物群落的程度仍未得到充分描述。
我们对来自52名健康女性的104对乳汁样本进行了二次分析，以研究家庭吸乳卫生习惯与母乳微生物群之间的关联。我们比较了使用个人设备挤出的样本，允许女性遵循其典型做法，记录吸乳器类型（封闭式与开放式系统）、吸乳前洗手以及收集套件清洁做法（自行操作）的差异。乳汁也在研究控制条件下使用医院级吸乳器和新的商业灭菌设备套件挤出（无菌操作），作为代表每位女性自身未改变的乳汁微生物群的对照。使用需氧培养和16S rRNA基因测序对微生物群组成进行表征。
在自行操作的乳汁样本中，个人吸乳器类型对母乳微生物群影响很小。只有22%的参与者进行了吸乳前洗手，这与较低的细菌计数相关。与使用手洗套件挤出的样本相比，使用家庭灭菌套件挤出的样本产生的总细菌和革兰氏阴性细菌计数更少，变形菌门的相对丰度更低。即使在没有吸乳前洗手的情况下，使用家庭灭菌套件挤出的自行操作乳汁样本的微生物群与无菌操作样本更相似（R = 0.36；P < 0.001）。
家庭卫生习惯，尤其是收集套件的清洁方法，会对母乳微生物群产生重大影响。收集套件的家庭灭菌可最大限度减少挤乳过程中母乳微生物群的变化。这些发现支持基于证据的吸乳卫生习惯建议，并强调需要进一步研究母乳微生物群中与吸乳相关的变化对婴儿健康的健康影响（如有）。
