Journal of Human Lactation最新文献

Background: Major pregnancy complications, such as hypertensive disorders of pregnancy, gestational diabetes mellitus, delivery of a small for gestational age infant, preterm delivery, and placental abruption, are associated with the development of Type II diabetes mellitus and cardiovascular disease. Improving breastfeeding longevity may reduce long-term risk for cardiovascular disease for those with major pregnancy complications. Metabolic syndrome (i.e., the presence of at least three specific cardiovascular disease risk factors) is an appropriate marker to assess future cardiovascular risk in the early postpartum.

Research aim: To determine whether lactation intensity in the first 6 months postpartum is associated with metabolic syndrome at 6 months postpartum among people who previously had a major pregnancy complication.Planned Analysis:This is a prospective observational cohort study is being conducted at a tertiary hospital in Adelaide, South Australia (ANZCTN12624001351505). We will be recruiting a total of 250 participants referred to a postpartum cardiovascular clinic after experiencing a major complication in pregnancy. To assess lactation intensity, participants complete online questionnaires on infant feeding patterns for 6 months postpartum. We will examine the relationship between lactation intensity and the development of metabolic syndrome at 6 months postpartum via binary logistic regression.

Discussion: Results of this study aid our understanding of the complex relationship between major pregnancy complications, early postpartum metabolic syndrome, and lactation. This data will inform whether interventions to support lactation should be leveraged to prevent primary cardiovascular disease in these high-risk pregnancy cohorts.

Background: While prior studies have established associations between specific factors and delayed onset of Lactogenesis II, critical gaps remain in understanding how the timing of lactogenesis initiation dynamically affects macronutrient levels within 72 hours postpartum, and whether modifiable factors alter these relationships.

Research aims: To validate known risk factors for delayed lactogenesis in a Chinese population; characterize time-specific macronutrient changes; and evaluate how modifiable factors (e.g., gestational diabetes mellitus) influence human milk composition.

Methods: In this prospective cohort study, 360 participants were interviewed during the first 24 hours postpartum in China. At 24-hour intervals, the onset of lactogenesis was determined based on maternal perception. The participants were divided into delayed onset of lactogenesis and onset of lactogenesis groups. Human milk samples were collected at 24, 48, and 72 hours postpartum, and their macronutrient content (lactose, fat, and protein) was determined using a human milk analyzer.

Results: Approximately 23.6% (n = 85) of participants experienced delayed lactogenesis, which was significantly associated with gestational diabetes mellitus, Cesarean delivery, and pre-pregnancy body mass index ≥ 25.0 kg/m² (odds ratio [95% confidence interval] = 2.32 [1.20, 4.50], 2.02 [1.20, 3.41], and 2.75 [1.23, 6.18], respectively).Lactose concentration was significantly lower in the delayed onset of lactogenesis group at 24 hours: Wald χ²(1) = 23.71, p < 0.001, and 48 hours: Wald χ²(1) = 8.26, p = 0.04, as well as in those with gestational diabetes at 24 hours postpartum: Wald χ²(1) = 9.60, p = 0.002.

Conclusion: Beyond confirming known risk factors for delayed lactogenesis in China, our identification of time-dependent lactose deficiency highlights the need for lactose concentration monitoring within the first 48 hours postpartum.

Background: Human milk contains messenger ribonucleic acid (mRNA), a key player in protein production and a source of gene expression information for understanding lactation physiology. The mRNA is renowned for its fragility and exists in several milk fractions, creating practical challenges for mRNA isolation and analysis. While research teams have developed protocols for the use of human milk samples in transcriptomic applications, it is unclear whether there are best practices in sample collection, storage, and processing procedures for the collection of the highest quality mRNA.

Research aim: We aim to review current practices in the collection, storage, and processing of human milk relevant for its use in transcriptomic applications (using mRNA) in the last 10 years.

Method: The PubMed database was systematically searched for publications addressing methodological considerations or the use of mRNA derived from human milk samples.

Results: Most sources described the collection of human milk from small cohorts of term mothers in a mature lactational stage. While fresh collection of human milk was common, some was frozen or preserved. Several centrifugation protocols exist, and considerations for collection, storage, and processing may vary by transcriptomic application. There is inconsistency in the description and reporting of mRNA quality used in analyses that obfuscates the determination of best practices for best mRNA quality.

Conclusions: Research into the effects of human milk collection, processing, and storage on mRNA quality metrics is warranted.

Background: Human milk sub-sampling protocols are used in lactation research to estimate milk composition, while minimizing interference with normal breastfeeding. However, macronutrient concentrations in human milk can be highly variable, and the accuracy of sub-sampling protocols for a single breastfeed is currently unknown.

Aim: We investigated the accuracy of three milk sub-sampling protocols for estimating the macronutrient concentrations of a complete feed: the mean of pre- and post-feed samples, pre-feed samples only, and post-feed samples only.

Method: In this observational study, macronutrient concentrations from each sub-sampling protocol were compared to the volume-weighted average of the complete pumping session, based on foremilk, bulk milk, and hindmilk samples from 15 mothers. Macronutrient concentrations of each milk fraction were measured with a human milk analyzer. Additionally, correlations between macronutrient concentrations and lactation characteristics were studied.

Results: Macronutrient concentrations from each sub-sampling protocol were strongly correlated with the volume-weighted average reference concentrations. Significant biases were found for the fat concentration (between -1.3 and +1.9 g/dl, depending on the protocol), but not for protein and carbohydrate concentrations.

Conclusions: For the fat concentration, none of the three sub-sampling protocols was accurate. The mean of pre- and post-feed samples could, however, be used for high-fat milk samples where measurement errors exceed the bias (+0.3 g/dl). Pre-feed or post-feed samples only should not be used to estimate the fat concentration of a complete feed. For proteins and carbohydrates, one milk sample taken at any moment in a breastfeed is sufficient to represent the concentration in the complete feed.

Background: Evidence on the beneficial effects of microorganisms in human milk is emerging. Obesity and gestational diabetes mellitus appear to be related to alterations in the maternal gut microbiota and human milk composition. However, knowledge about the influence of maternal obesity and gestational diabetes mellitus on the human milk microbiota remains limited.

Research aim: To summarize and systematically assess the evidence on the influence of obesity and gestational diabetes mellitus on the diversity and/or composition of the human milk microbiota.

Method: A systematic review following PRISMA guidelines was conducted. Searches were performed in the MEDLINE, Cochrane Database of Systematic Reviews, Web of Science, and EMBASE, as well as in ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform. The ROBINS-E tool was used to assess the risk of bias. Out of 1,473 studies identified and 24 protocol records, eight studies were selected for final analysis.

Results: Exposure to gestational diabetes mellitus and maternal obesity were associated with changes in the human milk microbiota's diversity and/or composition. Lactating women exposed to obesity had a higher prevalence of Staphylococcus and a lower prevalence of Bifidobacterium in their milk. Those exposed to gestational diabetes mellitus had a higher prevalence of Staphylococcus, Gemella, and Prevotella. Findings regarding bacterial phyla prevalence were inconclusive.

Conclusion: Based on the findings presented in this systematic review, it is not yet possible to draw definitive conclusions regarding the true influence of maternal obesity and/or gestational diabetes mellitus on the diversity or composition of the human milk microbiota.

Background: Perinatal loss is a time of intense grief for affected parents. Due to lactation physiology, bereaved mothers still experience the onset of lactation and are left with milk but no child to feed.

Aim: To explore what is known about the lactation experiences of (1) mothers and (2) support providers, including healthcare workers, milk banks, and families, during periods of perinatal bereavement.

Methods: A scoping review, guided by Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, was undertaken using two database searches to identify existing research (n = 24 studies). The research team extracted data from studies and categorized results into four categories that were developed after reading full texts: (1) Producing Milk, (2) Support, (3) Stopping Lactation, and (4) Donating Milk. Due to the large amount of qualitative data, additional qualitative analysis was conducted to identify six prominent themes: (1) Hurting, (2) Lacking, (3) Valuing, (4) Succeeding, (5) Connecting, and (6) Redeeming.

Results: Most of the included studies focused on mothers, and a limited number focused on support providers. Additionally, most studies were qualitative (19 of 24). Producing milk during bereavement was a way of connecting, while lactation support and stopping lactation were often characterized as lacking. Finally, donating milk was frequently perceived as redeeming. Across all categories, there were limited quantitative outcomes.

Conclusion: Bereaved lactation has predominantly been studied through qualitative research methods, with some common themes emerging. Quantitative research is needed to better understand the types and prevalence of lactation support provided during perinatal bereavement, as well as the donation patterns, barriers, and enablers of bereaved milk bank donors.

Background: Sexual and gender minority adults are increasingly growing their families and having children, yet there is limited information on the lactation experiences of sexual and gender minority parents.

Method: Using data from The PRIDE Study, a national cohort of sexual and gender minority adults in the United States, we examined patterns and correlates of lifetime breast/chestfeeding among sexual minority (i.e., lesbian, bisexual, queer) cisgender women, transgender women, transgender men, and gender diverse individuals who were parents.

Results: Our analysis included 1,562 parents aged 19-83 years with a median of two children (IQR 1-3). Among this population, 941 (60.2%) were sexual minority cisgender women, 232 (14.9%) transgender women, 199 (12.7%) transgender men, and 190 (12.2%) gender diverse parents assigned female at birth. Among 962 parents who had ever carried a pregnancy and delivered a child, sexual minority cisgender women were most likely to have ever breast/chestfed (91.7%), followed by gender diverse parents (88.8%) and transgender men (83.3%). No other demographic factors were associated with ever breast/chestfeeding. Few participants (6.7%) had ever breast/chestfed a child from another person's pregnancy. Ever having delivered a child and having an increasing number of children were associated with ever breast/chestfeeding a child from another person's pregnancy. In addition, seven (3%) transgender women had ever breast/chestfed a child.

Conclusions: In our cohort, rates of lifetime breast/chestfeeding were high among sexual and gender minority parents who had ever carried a pregnancy. Breast/chestfeeding provides important health and infant-parent bonding benefits in families where one or more parents has the interest in and capacity for lactation. Co-lactation and/or lactation induction may be particularly beneficial for sexual and gender minority families.

Background: Breastfeeding rates in Ireland are among the lowest in the world. Social support networks influence initiation and duration.

Research aim: To describe pregnant and postpartum women's encounters and experiences with health care professionals, family, or friends around breastfeeding in Ireland.

Method: Using a qualitative framework design, data were collected as part of a wider study. Online diary entries were collected between October 2021 and May 2022. Participants reflected on their breastfeeding encounters, focusing on timing, context, and feelings evoked about breastfeeding support. These a priori categories were the starting point for analysis.

Results: Participants (N = 27) produced a total of 91 diary entries entered while participants were from 13 weeks pregnant to 30 weeks postpartum. Most interactions recorded were with family members, friends, and lactation support providers. Three themes were identified: (1) Family Circle of Influence, (2) It Takes a Village, and (3) Maternity Service Providers. "Family Circle of Influence" included reflections on the influence of those closest to participants on their breastfeeding journey. Partners and female relatives were generally supportive and provided emotional support, despite having concerns about the decision to breastfeed. "It Takes a Village" covered troubleshooting feeding issues with friends and support groups. Experiences within this wider community group were influential, positively and negatively. "Maternity Service Providers" captured information sources, skills provision, and conflicting advice, which sometimes undermined maternal confidence.

Conclusion: Participants' breastfeeding journeys included encounters with family, social networks, and wider health services. Cumulative diary entries provided reflections on the emotional impact of supportive or undermining interactions on breastfeeding decisions.