Anatomy and physiology of lactation

Biomarker-based text messages to promote lactation success in mothers of critically Ill infants: a randomized controlled pilot study

OBJECTIVE

Infrequent breast pumping limits mother's own milk production in mothers of infants admitted to the neonatal intensive care unit. We aimed to determine the feasibility and benefit of biomarker-based personalized text messages on pumping frequency and milk sodium levels. A secondary aim examined lactation outcomes.

STUDY DESIGN

In this randomized controlled pilot study, 51 mothers were randomized to receive personalized text messages regarding pumping frequency or standard care.

RESULTS

There were no differences in pumped milk volume or sodium level, however, there was a trend towards the intervention group pumping more frequently, which was significant on day 5 (p = 0.035), and they lactated nearly 9 days longer. Post-hoc analysis found the intervention group tended to be more likely to pump ≥ 500 mL by day14 (p = 0.08), a marker of long-term lactation success.

CONCLUSION

Personalized biomarker-based text messages are feasible and may support lactation in mothers of critically ill infants.

Incidence and factors influencing delayed onset of lactation: a systematic review and meta-analysis

BACKGROUND

Breastfeeding has many benefits for mothers and infants. Lactogenesis II is one of the key steps in the implementation of breastfeeding. If lactogenesis II occurs more than 72 h after delivery, it is termed delayed onset of lactation (DOL). DOL is associated with decreased milk production, shortened breastfeeding time, and pathological neonatal weight loss. A comprehensive summary of the incidence and factors influencing DOL is needed to provide a basis for improving breastfeeding practices and health outcomes.

METHODS

Studies on the incidence and factors influencing DOL were retrieved from 13 Chinese and English databases (PubMed, Embase, Web of Science, Cochrane Library, CINAHL, etc.) from database inception to August 2023. Two researchers independently conducted the study screening, data extraction and quality evaluation. Stata 16.0 SE software was used for data analysis, and sensitivity analysis and publication bias tests were also performed. The qualitative description method was used to analyse studies that could not be combined quantitatively.

RESULTS

A total of 35 studies involving 19,176 parturients, including 4,922 who had DOL, were included. The mean Newcastle‒Ottawa scale score of the included studies was ≥ 6, indicating that the quality was relatively high. Finally, the incidence of DOL was 30%, and 13 factors influencing DOL with robust results and no publication bias were obtained: prepregnancy body mass index (overweight or obesity), gestational diabetes, gestational hypertension, thyroid disease during pregnancy, serum albumin levels (< 35 g/L), parity, (unscheduled) caesarean section, caesarean section history, daily sleep duration, gestational age, birth weight (< 2.5 kg), breastfeeding guidance and daily breastfeeding frequency. However, there were still six influencing factors with undetermined associations: age, gestational weight gain, birth weight (≥ 4 kg), anxiety, time of first breastfeeding session (maternal separation) and breast massage or treatment.

CONCLUSIONS

The incidence of DOL is high. Clinicians should pay attention to parturients at high risk of DOL and formulate targeted prevention strategies according to the influencing factors to reduce the occurrence of DOL and promote better maternal and infant outcomes.

TRIAL REGISTRATION

PROSPERO (ID: CRD42023458786), September 10, 2023.

Comparison of Breastfeeding Success by Mode of Delivery

OBJECTIVE

This article identifies how mode of delivery and the presence of labor affect the initiation and effectiveness of breastfeeding.

STUDY DESIGN

This is a retrospective cohort study of breastfeeding success after vaginal delivery, cesarean section after labor, and scheduled cesarean section in term, singleton deliveries in nulliparous patients at a large academic institution from 2017 to 2018. Exclusion criteria included major postpartum complications requiring admission to the surgical intensive care unit or neonatal intensive care unit, general anesthesia, and major fetal anomalies. Breastfeeding success in the immediate postpartum period, defined as the first 2 to 3 days postpartum prior to hospital discharge, was measured by the presence of breastfeeding, the need for formula supplementation, the average number of breastfeeding sessions per day, the average amount of time spent at each breastfeeding session, the average number of newborn stools and wet diapers produced daily, and the neonatal percentage in weight loss over the first 2 to 3 days of life. Multivariable linear and logistic regression were used to assess the association between mode of delivery and markers of breastfeeding success after adjusting for potential confounders. A Tukey's post hoc analysis with pairwise comparisons was performed to assess differences in breastfeeding outcomes between vaginal delivery, scheduled cesarean section, and cesarean section after labor.

RESULTS

A total of 2,966 women met inclusion criteria during the study period, 1,936 (65.3%) of whom underwent spontaneous vaginal delivery, 415 (14.0%) of whom delivered by scheduled cesarean section, and 615 (20.7%) of whom underwent cesarean section after labor. There were significant differences in maternal age, obesity, race/ethnicity, insurance status, gestational age at delivery, birth weight, and 1-minute Apgar's score less than 7 between vaginal delivery, scheduled cesarean section, and cesarean section after labor. There were also significant differences between indication for oxytocin, type of anesthesia, and postpartum hemorrhage between the three groups. After controlling for these factors, women who underwent vaginal delivery were more likely to have infants with decreased need for formula supplementation (adjusted odds ratio [aOR] = 1.71, 95% confidence interval [CI]: 1.52-1.93) and were less likely to switch from breast to formula feeding (aOR = 1.71, 95% CI: 1.04-1.31) in comparison to women who delivered via cesarean section in labor or scheduled cesarean section. The infants of these women also had an increased number of breastfeeding sessions on average (β = 0.06, p = 0.002), required fewer number of daily formula feedings (β = 0.14, p < 0.001), and experienced a smaller percentage in neonatal weight loss over the first 2 to 3 days of life (β = 0.18, p < 0.001) compared to those born after cesarean section and cesarean section after labor. These women comparatively required less time at each breastfeeding session (β = 0.06, p = 0.005), and produced fewer wet diapers and stools on average (β = 0.12, p < 0.001 and β = 0.12, p < 0.001, respectively). On post hoc analysis with pairwise comparisons, and on separate sensitivity analysis of only women who underwent cesarean delivery, there was no difference in breastfeeding outcome measures between scheduled cesarean section and cesarean section in labor.

CONCLUSION

Women who deliver by cesarean section, despite the presence or absence of labor, are less likely to maintain exclusive breastfeeding postpartum and are more likely to require formula supplementation. These women may need more support with breastfeeding after surgery in order to experience similar benefits for neonatal growth and weight gain.

KEY POINTS

· Women who deliver by cesarean section are less likely to maintain exclusive breastfeeding.. · Women who deliver by cesarean section are more likely to require formula supplementation.. · Women may need more support with breastfeeding after cesarean delivery..

Dual role of pregnancy in breast cancer risk

Reproductive history is one of the strongest risk factors for breast cancer in women. Pregnancy can promote short-term breast cancer risk, but also reduce a woman's lifetime risk of breast cancer. Changes in hormone levels before and after pregnancy are one of the key factors in breast cancer risk. This article summarizes the changes in hormone levels before and after pregnancy, and the roles of hormones in mammary gland development and breast cancer progression. Other factors, such as changes in breast morphology and mammary gland differentiation, changes in the proportion of mammary stem cells (MaSCs), changes in the immune and inflammatory environment, and changes in lactation before and after pregnancy, also play key roles in the occurrence and development of breast cancer. This review discusses the dual effects and the potential mechanisms of pregnancy on breast cancer risk from the above aspects, which is helpful to understand the complexity of female breast cancer occurrence.

Variation in maternal lactation practices associated with changes in diurnal maternal inflammation

While the importance of human milk in shaping infant immune function is well established, the impact of at-the-nipple (ATN) breastfeeding on maternal immune status has been understudied. Since lactation evolved to support infant survival and boost maternal fitness, we predict that ATN breastfeeding will confer benefits on maternal immune function. We measure the absolute and relative frequency of different infant feeding methods (ATN breastfeeding, pumping, donated milk, other supplementation) used by postpartum women in Seattle, WA (USA). We implement Bayesian modeling to estimate the effects of ATN breastfeeding on diurnal change in secretion rate of "pro-inflammatory" salivary cytokines and C-reactive protein (CRP). Our results show that most mothers in our sample used a variety of infant feeding methods, with pumping as the most common alternative to ATN breastfeeding. We find that ATN breastfeeding is associated with non-linear effects on diurnal IL-8 and CRP. Furthermore, we find that women who report zero versus ubiquitous ATN breastfeeding exhibit opposing diurnal patterns in CRP secretion rate. This study provides evidence that variation in maternal lactation practices corresponds to differences in maternal immune responses, highlighting how measuring lactation as a continuous variable can further enhance understanding of postpartum maternal physiology.

Breast Imaging and Intervention during Pregnancy and Lactation

Physiologic changes that occur in the breast during pregnancy and lactation create challenges for breast cancer screening and diagnosis. Despite these challenges, imaging evaluation should not be deferred, because delayed diagnosis of pregnancy-associated breast cancer contributes to poor outcomes. Both screening and diagnostic imaging can be safely performed using protocols based on age, breast cancer risk, and whether the patient is pregnant or lactating. US is the preferred initial imaging modality for the evaluation of clinical symptoms in pregnant women, followed by mammography if the US findings are suspicious for malignancy or do not show the cause of the clinical symptom. Breast MRI is not recommended during pregnancy because of the use of intravenous gadolinium-based contrast agents. Diagnostic imaging for lactating women is the same as that for nonpregnant nonlactating individuals, beginning with US for patients younger than 30 years old and mammography followed by US for patients aged 30 years and older. MRI can be performed for high-risk screening and local-regional staging in lactating women. The radiologist may encounter a wide variety of breast abnormalities, some specific to pregnancy and lactation, including normal physiologic changes, benign disorders, and malignant neoplasms. Although most masses encountered are benign, biopsy should be performed if the imaging characteristics are suspicious for cancer or if the finding does not resolve after a short period of clinical follow-up. Knowledge of the expected imaging appearance of physiologic changes and common benign conditions of pregnancy and lactation is critical for differentiating these findings from pregnancy-associated breast cancer. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Milk Transmission of Mammalian Retroviruses

The transmission of viruses from one host to another typically occurs through horizontal or vertical pathways. The horizontal pathways include transmission amongst individuals, usually through bodily fluids or excretions, while vertical transmission transpires from mother to their offspring, either during pregnancy, childbirth, or breastfeeding. While there are more than 200 human pathogenic viruses to date, only a small number of them are known to be transmitted via breast milk, including cytomegalovirus (CMV), human immunodeficiency virus type 1 (HIV-1), and human T cell lymphotropic virus type 1 (HTLV-1), the latter two belonging to the family Retroviridae. Breast milk transmission is a common characteristic among mammalian retroviruses, but there is a lack of reports summarizing our knowledge regarding this route of transmission of mammalian retroviruses. Here, we provide an overview of the transmission of mammalian exogenous retroviruses with a focus on Orthoretrovirinae, and we highlight whether they have been described or suspected to be transmitted through breast milk, covering various species. We also elaborate on the production and composition of breast milk and discuss potential entry sites of exogenous mammalian retroviruses during oral transmission.

The impact of swaddling upon breastfeeding: A critical review

INTRODUCTION

Many parents swaddle their infants to promote sleep and reduce night-waking, however lack of definitive evidence about the pros and cons of swaddling when breastfeeding hinders postnatal recommendations regarding this infant care practice. This review critically examines research conducted on the impact of swaddling upon breastfeeding.

METHODS

Only two recent studies on swaddling outcomes have reported infant feed-type, therefore the purpose of this paper is to consider the known effects of swaddling on breastfeeding babies and their mothers. We interpret the existing literature on swaddling in terms of impact on breastfeeding physiology and behaviour during the immediate post-natal period, and as infancy progresses.

RESULTS

Infants swaddled immediately after birth show a delay in initial breastfeeding, less successful suckling at the breast, reduced intake of breastmilk and greater weight loss compared to un-swaddled babies. Swaddling visually obscures feeding cues and reduces crying, thereby eliminating two key feeding prompts typically used by parents/carers.

CONCLUSIONS

As swaddled babies cry less, and are fed less frequently than un-swaddled babies some clinical trials position swaddling as a 'novel weight regulation tool' to combat obesity. However, in the case of breastfed babies, by reducing feed frequency swaddling may impede maternal milk production and thereby infant growth.

Effect of lullaby on volume, fat, total protein and albumin concentration of breast milk in premature infants' mothers admitted to NICU: a randomized controlled trial

Background

Listening to music can reduce or manage stress, fatigue, and accompanying symptoms in mothers. Music increases oxytocin secretion which affects breast milk. This study aimed to examine the effect of lullaby on volume, fat, total protein and albumin concentration of breast milk in mothers of premature infants admitted to the NICU.

Methods

This clinical trial was performed on 100 primiparous mothers whose premature infants were hospitalized in the NICU of Ayatollah Rouhani Hospital from January 2020 to December 2020. Using block randomization method, the participants were divided into three groups: control (A), playing lullaby for mother (B) and playing lullaby for a mother while holding a photo of her own baby (C). The mothers of the intervention groups listened to lullabies through headphones for 30 minutes every morning for 6 days. On the first and the sixth day of birth, the volume of breast milk (ml) and two milliliters of breast milk samples of all three groups were measured and compared in terms of fat, albumin concentration and total protein (mg/DL). ANOVA, Paired T-Test and ANCOVA model (the included variables were: basic value of dependent variable, group type, Maternal age, Birth weight, Gestational age and Maternal weight) was used for analytical statistics.

Results

The difference between the mean compositions of breast milk before and after the intervention in three groups of A, B and C: in terms of the breast milk volume were 66.33 ± 4.80, 71.30 ± 4.18 and 75.91 ± 6.80 ml; in terms of triglyceride level was 177.84 ± 50.57, 210.72 ± 34.55 and 224.17 ± 12.97 mg/DL, cholesterol level was 14.57 ± 3.70, 21.96 ± 3.82 and 26.26 ± 5.16 mg/DL, albumin concentration was 0.90 ± 0.30, 1.22 ± 0.19 and 1.46 ± 0.28 mg/DL and total protein level was 1.61 ± 0.61, 2.20 ± 0.57 and 2.72 ± 0.30 mg/DL. Finally, the results of ANCOVA analysis for the effects of the intervention, taking into account the baseline values, showed that the intervention was effective and had the greatest effect on cholesterol levels.

Conclusion

In this small trial, there was a statistically significant association between trial arm and biochemical composition of breastmilk though further studies are needed to see if these changes result in meaningful clinical outcomes to the infant.

Trial registration

IRCT, IRCT20191114045439N1. Registered 14 January 2020- prospective, https://en.irct.ir/trial/43671

Supplementary Information

The online version contains supplementary material available at 10.1186/s13006-022-00511-7.

Cow's Milk Antigens Content in Human Milk: A Scoping Review

The functionality of breast milk in terms of immunity is well-known. Despite this, a significant proportion of breastfed infants exhibit sensitization to different potentially allergenic proteins and clinical reactivity (including anaphylaxis) early in life and before the introduction of complementary feeding for the first time. The potential induction of early oral tolerance to overcome early allergic sensitization through exposure to allergens in breast milk also remains controversial and not yet well-established. The objective of this scoping review is to provide a critical appraisal of knowledge about the content of cow's milk antigens in human milk. The amount of dietary derived milk antigens found in human milk and the analytical methodologies used to detect and quantify these antigens, the allergic status of the mother, the stage of lactation, the time of sampling (before or after ingestion of food), and the impact of human milk allergen on the infant were the outcomes that were assessed. Allergy risk was explored in all reviewed studies and could help to better elucidate its role in the context of allergic disease development. According to the included literature, we can conclude that there are mainly fragments derived from bovine proteins in human milk, and the presence of potentially allergenic molecules is greater in the milk of mothers with an allergic tendency. A clear relationship between maternal diet and allergen content in breast milk could not be firmly concluded though. Also, infants receiving milk from human milk banks, where donor milk is pasteurized for preservation, may be subject to greater risk of allergy development, especially for β-lactoglobulin.

Human milk: From complex tailored nutrition to bioactive impact on child cognition and behavior

Human milk is a highly complex liquid food tailor-made to match an infant's needs. Beyond documented positive effects of breastfeeding on infant and maternal health, there is increasing evidence that milk constituents also impact child neurodevelopment. Non-nutrient milk bioactives would contribute to the (long-term) development of child cognition and behavior, a process termed 'Lactocrine Programming'. In this review we discuss the current state of the field on human milk composition and its links with child cognitive and behavioral development. To promote state-of-the-art methodologies and designs that facilitate data pooling and meta-analytic endeavors, we present detailed recommendations and best practices for future studies. Finally, we determine important scientific gaps that need to be filled to advance the field, and discuss innovative directions for future research. Unveiling the mechanisms underlying the links between human milk and child cognition and behavior will deepen our understanding of the broad functions of this complex liquid food, as well as provide necessary information for designing future interventions.

Investigation of the effect of metoclopramide on proliferation signal molecules in breast tissue

Metoclopramide (MCP) is a drug that has been widely used in recent years due to its hyperprolactinaemia effect on mothers during breastfeeding. The aim of this study was to investigate the proliferative changes that MCP may cause in the maternal breast tissue. In this study, 18 Wistar albino young-adult breastfeeding mothers with their offspring were divided into three groups: control group, low-dose MCP-applied group and high-dose MCP-applied group. The experiment was carried out during the lactation period and at the end of 21 days. Prolactin, BrdU and Ki-67 breast tissue distributions were evaluated by immunohistochemistry, and tissue levels were evaluated biochemically by the ELISA method. According to ELISA and immunohistochemistry results in breast tissue, there was no significant difference between Ki-67 and BrdU results in all groups. Metoclopramide did not change the expression of proliferation molecules Ki-67 and BrdU in breast tissue. These results suggested that while metoclopramide increases breast proliferation, it does not have the risk of transforming the tissue into a tumour.

Prepregnancy Body Mass Index Is Associated with Time-Dependent Changes in Secretory Activation Measures During the First 7 Days Postpartum in Breast Pump-dependent Mothers of Premature Infants

Background: Little is known about the biology of secretory activation (SA) in overweight and obese (OW/OB) mothers who are breast pump dependent with a premature infant in the neonatal intensive care unit. Objective: To compare time-dependent changes in daily pumped milk volume, maternal milk sodium (Na) concentration, and Na-to-potassium (K) ratios (Na:K) in the first 14 days postpartum in breast pump-dependent mothers with prepregnancy body mass index (BMI) <27 and BMI ≥27 kg/m². Design/Methods: This secondary analysis for 39 subjects, 44% (n = 17) with prepregnancy BMI <27 and 56% (n = 22) with BMI ≥27, included transformed data of outcome measures, chi-square, t-tests, and growth curve models. Results: For days 1-7, daily pumped milk volume increased significantly more rapidly for mothers with BMI <27 (65.82 mL/d) versus BMI ≥27 (33.08 mL/d), but the daily rate of change in pumped milk volume during days 8-14 was not statistically different. Daily milk Na concentration decreased significantly faster in BMI <27 (-3.93 mM/d) versus BMI ≥27 (-2.00 mM/day) during days 1-7, but was not significantly different for days 8-14. No statistical differences were noted for Na:K ratio for either time period. Conclusion: These data add biologic evidence to previous research, suggesting delayed or impaired SA in OW/OB mothers, and suggest that the window of opportunity for research and clinical interventions is days 1-7 postpartum in this population.

Parity predicts allonursing in a cooperative breeder

In some mammals that breed cooperatively, nonbreeding female helpers nurse offspring born to the breeding female in their group, a process known as allonursing. Previous laboratory studies have suggested that primiparous and multiparous females (those that have successfully given birth once or more, respectively) are more likely to contribute to allonursing than nulliparous females (those that have not given birth). In contrast, few field studies have been able to demonstrate whether breeding experience, or parity, affects the likelihood or duration of allonursing. In this study, we investigated whether the likelihood and duration of allonursing by subordinate female meerkats (Suricata suricatta) were associated with variations in their parity (number of pregnancies reaching a viable gestational age) and their immediate pregnancy status. Comparisons showed that nonpregnant nulliparous females were less likely to allonurse than nonpregnant primiparous and multiparous females, although parity was not related to variation in allonursing duration. Parity may enhance the expression of maternal behavior when exposed to foster pups, especially since mammary gland development has been shown to be directly associated with parity in other mammals.

Modern, exogenous exposures associated with altered mammary gland development: A systematic review

BACKGROUND

Many women report low milk supply as the reason for premature breastfeeding cessation. Altered mammary gland development may impact a woman's lactation ability.

OBJECTIVE

This review identifies modern exogenous exposures which alter mammary gland development during embryonic life, puberty and pregnancy.

METHODS

A systematic review was undertaken whereby Medline, CINAHL and Embase articles published from January 1, 2005 to November 20, 2020 were searched using the keywords puberty or embry* or fetal or foetal or foetus or fetus or pregnan* or gestation* AND "mammary gland development" or "breast development" or "mammary development" or "mammary gland function" or "mammary function" or "insufficient glandular tissue" or "mammary hypoplasia" or "breast hypoplasia" or "mammary gland hypoplasia" or "tubular breast*" or "tuberous breast*" or "glandular tissue" or "breast composition" or "mammary composition" or "mammary gland composition". After initial screening of 1207 records, 60 full texts were assessed for eligibility; 6 were excluded due to lack of information about exposure or outcome, leaving 54 studies.

RESULTS

The review included results from 52 animal (rats and mice, monkeys, rabbits, sheep, goats pigs and cows) and 2 human studies. Various endocrine disrupting chemicals and an obesogenic diet were found to be associated with altered mammary gland morphology during key development stages.

CONCLUSIONS

To improve lactation outcomes, future studies need to focus on lactation as the endpoint and be conducted in a standardised manner to allow for a more significant contribution to the literature that allows for better comparison across studies.

Animal Models for In Vivo Lactation Studies: Anatomy, Physiology and Milk Compositions in the Most Used Non-Clinical Species: A Contribution from the ConcePTION Project

Simple Summary

Nowadays, the importance of breastfeeding has been very well recognized not only by the scientific world but also by public opinion. Such awareness has nonetheless put a lot of pressure on women under chronic pharmacological medication, or that simply need to alleviate common post-partum health issues, due to the lack of scientific data regarding the potential transfer to the offspring during lactation. In such a scenario, the ConcePTION project aims at creating a trusted ecosystem that can efficiently generate and disseminate reliable evidence-based information regarding the effects of medications used during pregnancy and breastfeeding to women and their healthcare providers. Due to the need for a reliable animal species to obtain scientific data, the present review summarizes the main features contributing to the lactation process in the most commonly used laboratory animal species.

Abstract

The present review aims to summarize the main features of mammary gland anatomy, and the physiology of lactation and colostrum/milk in the most commonly used animal species for regulatory toxicity. The final goal is the selection of a preferred animal species to be enrolled in studies investigating the potential transfer of drugs and exogenous molecules through milk, within the Innovative Medicines Initiative (IMI) funded project ConcePTION. Reference data regarding humans were also collected and analyzed in order to highlight critical similarities and differences with the studied species. Additional practical considerations were also taken into account, such as ethical consideration regarding the chosen species which affects the group size, financial implications and technical feasibility of lactation trials (e.g., ease of sampling, volume of sampling, husbandry requirements and scientific recognition). In conclusion, the present analysis of the literature confirms the complexity of the decisional process behind the choice of an animal model for in vivo trials. For some of the evaluated species, data were either poor or missing, highlighting the necessity to generate more physiological background studies for species that are routinely used in laboratory settings. Overall, when taking into consideration ethical factors, feasible group size, milk volume and ease of milk collection, and physiological similarities with humans, minipigs seem to represent the most appropriate choice.

Maternal production of milk for infants in the neonatal intensive care unit

Mother's own milk (MOM) feeding is a cost-effective strategy to reduce risks of comorbidities associated with prematurity and improve long-term health of infants hospitalized in the Neonatal Intensive Care Unit (NICU). Significant racial and socioeconomic disparities exist in MOM provision in the NICU, highlighting the importance of developing strategies to reduce these disparities. Mothers of infants in the NICU experience many health concerns which may negatively impact lactation physiology. Objective measures of lactation physiology are limited but may assist in identifying mothers at particular risk. Several strategies to assist mothers of hospitalized infants are essential, including maternal education, qualified lactation professionals, early and frequent milk expression with a hospital-grade double electric breast pump, and providing support for transitioning to direct breastfeeding prior to discharge from the NICU.

Quantitative imaging of tongue kinematics during infant feeding and adult swallowing reveals highly conserved patterns

Tongue motility is an essential physiological component of human feeding from infancy through adulthood. At present, it is a challenge to distinguish among the many pathologies of swallowing due to the absence of quantitative tools. We objectively quantified tongue kinematics from ultrasound imaging during infant and adult feeding. The functional advantage of this method is presented in several subjects with swallowing difficulties. We demonstrated for the first time the differences in tongue kinematics during breast- and bottle-feeding, showing the arrhythmic sucking pattern during bottle-feeding as compared with breastfeeding in the same infant with torticollis. The method clearly displayed the improvement of tongue motility after frenotomy in infants with either tongue-tie or restrictive labial frenulum. The analysis also revealed the absence of posterior tongue peristalsis required for safe swallowing in an infant with dysphagia. We also analyzed for the first time the tongue kinematics in an adult during water bolus swallowing demonstrating tongue peristaltic-like movements in both anterior and posterior segments. First, the anterior segment undulates to close off the oral cavity and the posterior segment held the bolus, and then, the posterior tongue propelled the bolus to the pharynx. The present methodology of quantitative imaging revealed highly conserved patterns of tongue kinematics that can differentiate between swallowing pathologies and evaluate treatment interventions. The method is novel and objective and has the potential to advance knowledge about the normal swallowing and management of feeding disorders.

Recurrent Violence, Violence with Complications, and Intimate Partner Violence Against Pregnant Women and Breastfeeding Duration

Background: Few studies have investigated the association between violence against pregnant women in terms of recurrence, complications, and perpetrators of violence, and breastfeeding duration. This study verifies whether recurrent violence, violence with pregnancy complications, and intimate partner violence (IPV) against pregnant women are associated with shorter exclusive breastfeeding up to the infant's 6th month and breastfeeding up to the 12th month of life. Materials and Methods: A cohort study with a convenience sample of 1,146 pregnant women was performed. Follow-up assessments were conducted at birth, and at 12-36 months. Survival analysis was used to verify whether recurrent violence, violence with pregnancy complications, and IPV were associated with reduced duration of exclusive breastfeeding and breastfeeding. Results: The adjusted Cox regression revealed no difference regarding exclusive breastfeeding duration among mothers exposed or not exposed to violence and according to who perpetrated the violence. The risk of an infant not being breastfed within the first 12 months of life increased in cases of violence before/during pregnancy (95% confidence interval [CI] = 1.03-1.88), recurrent psychological/physical/sexual violence during pregnancy (95% CI = 1.11-1.92), recurrent psychological violence (95% CI = 1.05-1.96), and recurrent physical/sexual violence (95% CI = 1.01-2.39). Violence with pregnancy complications (95% CI = 0.94-2.22) was not associated with breastfeeding interruption. Similar risks of breastfeeding interruption were observed for IPV (95% CI = 0.96-1.87) and violence perpetrated by other family members (95% CI = 0.83-1.89). Conclusions: We observed a shorter breastfeeding duration up to 12 months of life in cases of recurrent violence.

Early Term Delivery and Breastfeeding Outcomes

OBJECTIVE

Higher rates of adverse outcomes have been reported for early term (37 0 to 38 6 weeks) versus full term (≥ 39 0 weeks) infants, but differences in breastfeeding outcomes have not been systematically evaluated. This study examined breastfeeding initiation and exclusivity in early and full term infants in a large US based sample.

METHODS

This secondary analysis included 743 geographically- and racially-diverse women from the Measurement of Maternal Stress Study cohort, and 295 women from a quality assessment at a hospital-based clinic in Evanston, IL. Only subjects delivering ≥ 37 weeks were included. Initiation of breastfeeding (IBF) and exclusive breastfeeding (EBF) were assessed via electronic medical record review after discharge. Associations of IBF and EBF with early and full term delivery were assessed via univariate and multivariate logistic regression.

RESULTS

Among 872 women eligible for inclusion, 85.7% IBF and 44.0% EBF. Early term delivery was not associated with any difference in frequency of IBF (p = 0.43), but was associated with significantly lower odds of EBF (unadjusted OR 0.61, 95% CI 0.466, 0.803, p < 0.001). This association remained significant (adjusted OR 0.694, 95% CI 0.515, 0.935, p = 0.016) after adjusting for maternal diabetes, hypertensive disorders of pregnancy, cesarean delivery, maternal age, race/ethnicity, parity, Medicaid status, NICU admission, current smoking, and delivery hospital.

CONCLUSIONS FOR PRACTICE

Despite comparable breastfeeding initiation frequencies, early term infants were significantly less likely to be exclusively breastfed compared to full term infants. These data suggest that women with early term infants may benefit from counseling regarding the potential for breastfeeding difficulties as well as additional breastfeeding support after delivery.

Mother's Own Milk Feeding and Severity of Respiratory Illness in Acutely Ill Children: An Integrative Review

PROBLEM

Breastfed infants experience less severe infections while actively breastfeeding. However, little is known about whether a history of prior breastfeeding affects severity of illness. Therefore, the purpose of this integrative review was to examine the relationship between previous exposure to mother's own milk (MOM) feeding and severity of respiratory infectious illness in infants and children.

ELIGIBILITY CRITERIA

Studies meeting the following criteria were included: human subjects, term birth, ages 0-35 months at time of study, diagnosis of pneumonia, bronchiolitis or croup, MOM feeding, and statistical analyses reporting separate respiratory infectious illness outcomes when combined with other infections.

SAMPLE

Twelve articles met eligibility criteria.

RESULTS

Major findings were inconsistent definitions of both dose and exposure period of breastfeeding and the severity of illness. In particular, the severity of illness measure was limited by the use of proxy variables such as emergency room visits or hospitalizations that lacked reliability and validity. However, given this limitation, the data suggested that exclusive breastfeeding for four to six months was associated with reduced severity of illness as measured by frequency of visits to the primary care provider office, emergency department or hospitalization.

CONCLUSIONS

Future research in this area should incorporate reliable and valid measures of MOM dose and exposure period and severity of illness outcomes in the critically ill child.

IMPLICATIONS

Among many positive outcomes associated with breastfeeding, an additional talking point for encouragement of exclusive breastfeeding for four to six months may be protective against severe respiratory infectious illness after cessation of breastfeeding.

Successful Full Lactation Achieved by Mothers of Preterm Infants Using Exclusive Pumping

Background: Some mothers of preterm infants suffer from difficulties in initiating and maintaining adequate milk production. This study was designed to investigate the milk production in mothers of preterm infants using hospital-grade breast pumps and to study the nutrient content of their milk. Methods: This was an observational prospective study. Mothers of preterm infants with gestational age < 32 weeks or birth weight < 1,500 g who were admitted to our hospital from August 2016 to December 2017 were recruited. A pumping diary and a questionnaire were completed by mothers (n = 30). Milk samples from before, during, and after each pumping session on days 7 and 14 postpartum were analyzed. Results: The median time to onset of lactogenesis II was 75.4 h. Mean milk output increased gradually, meeting key thresholds of 350 g/d on day 6, 500 g/d on day 8, and close to 750 g/d on day 14. Then, all mean milk outputs were over 750 g/d. The mean milk output exceeded the mean feeding volume on days 7, 14, 21, 28, 35, and 42. Mothers using hospital-grade breast pumps had more cumulative milk production compared with mothers using hand expression. The milk yield on days 7 and 14 were positively correlated to that on days 21, 28, 35, and 42. Milk outputs on days 7, 14, and 42 of mothers with a pumping frequency of ≥ 6 times/d were greater than mothers with a pumping frequency of < 6 times/d. Threshold values for milk output on day 7 (cut-off, 406.8 g/d; sensitivity, 68.2%; specificity, 100%) and day 14 (cut-off, 518.0 g/d; sensitivity, 81.8%; specificity, 100%) were identified as predicting a milk output of more than 750 g/d on day 42. Fat and energy levels were higher in hind-milk than fore- or mixed-milk on days 7 and 14. Those who pumped ≥ 6 times/d had higher levels of fat, carbohydrate, and energy in their milk on day 7. Conclusion: Most preterm infants' mothers using a hospital-grade pump with a pumping frequency of ≥ 6 times/d can reach full lactation successfully. Nutrient analysis of the human milk should be performed.

Donor Milk Policies for Level 1 Newborn Care: A Descriptive Analysis

Background and Objectives: Providing pasteurized donor human milk (DHM) to healthy newborns is an emerging practice. The content of hospital policies that govern this practice is unknown. Materials and Methods: We collected policies from 15 Northeast U.S. hospitals through (1) a 2017 survey on DHM use and (2) an e-mail listserv of levels 1 and 2 newborn care staff maintained by a regional milk bank. Two authors reviewed each policy and identified how they addressed three predetermined themes: who is eligible to receive DHM, how DHM is used and described, and how lactation is supported. Responses were compared, discussed, and reconciled. Level 1 newborn care was defined as basic care for healthy newborns ≥35 weeks' gestation. Results: Thirteen of 15 policies stated criteria for DHM eligibility, most commonly as a bridge until mother's supply comes in (73%) or for infant medical conditions (67%). All required consent for DHM. Most did not limit number of days infants could receive DHM (60%). Nine specified that DHM be discarded 24 hours after thaw, whereas five recommended discarding at 48 hours. Although many (53%) policies endorsed human milk as the preferred diet for newborns, only 27% specifically endorsed DHM as the preferred supplementation type. Parent education (73%) was emphasized, but few (27%) discussed the importance of establishing mother's milk supply. Conclusions: Many DHM policies address eligibility criteria for receiving DHM and show how to provide DHM, but few address how to support lactation while DHM is provided, which may be crucial for optimizing long-term breastfeeding outcomes.

Effect of colostrum given within the 12 hours after birth on feeding outcome, morbidity and mortality in very low birth weight infants: a prospective cohort study

The current study aims to compare the feeding outcome, morbidity and mortality in very low birth weight (VLBW) infants who received early colostrum (<12 hours of life) and those who did not. All VLBW infants admitted to neonatal intensive care unit (NICU) were eligible for the study. Eligible infants were enrolled after obtaining written informed consent from either of the parents. Newborns who received colostrum within the first 12 hours after birth formed the study cohort and all others the control cohort. Both cohorts were followed till discharge from NICU. During the study period, 205 VLBW infants were admitted in NICU of whom 171 (83%) infants were enrolled in the study. Both study groups were comparable for mean birth weight, mean gestation and male sex. The proportion of infants with abnormal Doppler was significantly higher in the control group. All outcomes were adjusted for antenatal Doppler abnormalities. The primary outcome of time to reach full feeds in the study population was 6.90 ± 4.4 days as compared to 9.80 ± 4.86 days in the control group with a significant weighted mean difference of -2.4 (-0.8 to -3.9) days. Duration of total parenteral nutrition (TPN) days and mortality were all lower in the study cohort. Risk of sepsis and necrotising enterocolitis was similar in the both groups. Enteral colostrum within first 12 hours of birth in VLBW infants reduces the time to reach full feeds, TPN days and mortality.

What Evidence Do We Have for Pharmaceutical Galactagogues in the Treatment of Lactation Insufficiency?-A Narrative Review

Inadequate breast milk supply is a frequently reported reason for early discontinuation of breastfeeding and represents a critical opportunity for intervening to improve breastfeeding outcomes. For women who continue to experience insufficient milk supply despite the utilisation of non-pharmacological lactation support strategies, pharmacological intervention with medications used to augment lactation, commonly referred to as galactagogues, is common. Galactagogues exert their pharmacological effects through altering the complex hormonal milieu regulating lactation, particularly prolactin and oxytocin. This narrative review provides an appraisal of the existing evidence regarding the efficacy and safety of pharmaceutical treatments for lactation insufficiency to guide their use in clinical practice. The greatest body of evidence surrounds the use of domperidone, with studies demonstrating moderate short-term improvements in breast milk supply. Evidence regarding the efficacy and safety of metoclopramide is less robust, but given that it shares the same mechanism of action as domperidone it may represent a potential treatment alternative where domperidone is unsuitable. Data on remaining interventions such as oxytocin, prolactin and metformin is too limited to support their use in clinical practice. The review provides an overview of key evidence gaps and areas of future research, including the impacts of pharmaceutical galactagogues on breast milk composition and understanding factors contributing to individual treatment response to pharmaceutical galactagogues.

Milk lipid regulation at the maternal-offspring interface

Milk lipids provide a large proportion of energy, nutrients, essential fatty acids, and signaling molecules for the newborns, the synthesis of which is a tightly controlled process. Dysregulated milk lipid production and composition may be detrimental to the growth, development, health and survival of the newborns. Many genetically modified animal models have contributed to our understanding of milk lipid regulation in the lactating mammary gland. In this review, we discuss recent advances in our knowledge of the mechanisms that control milk lipid biosynthesis and secretion during lactation, and how maternal genetic and dietary defects impact milk lipid composition and consequently offspring traits.

The Mammary Microenvironment in Mastitis in Humans, Dairy Ruminants, Rabbits and Rodents: A One Health Focus

The One Health concept promotes integrated evaluation of human, animal, and environmental health questions to expedite advances benefiting all species. A recognition of the multi-species impact of mastitis as a painful condition with welfare implications leads us to suggest that mastitis is an ideal target for a One Health approach. In this review, we will evaluate the role of the mammary microenvironment in mastitis in humans, ruminants and rabbits, where appropriate also drawing on studies utilising laboratory animal models. We will examine subclinical mastitis, clinical lactational mastitis, and involution-associated, or dry period, mastitis, highlighting important anatomical and immunological species differences. We will synthesise knowledge gained across different species, comparing and contrasting disease presentation. Subclinical mastitis (SCM) is characterised by elevated Na/K ratio, and increased milk IL-8 concentrations. SCM affecting the breastfeeding mother may result in modulation of infant mucosal immune system development, whilst in ruminants notable milk production losses may ensue. In the case of clinical lactational mastitis, we will focus on mastitis caused by Staphylococcus aureus and Escherichia coli. Understanding of the pathogenesis of involution-associated mastitis requires characterization of the structural and molecular changes occurring during involution and we will review these changes across species. We speculate that milk accumulation may act as a nidus for infection, and that the involution 'wound healing phenotype' may render the tissue susceptible to bacterial infection. We will discuss the impact of concurrent pregnancy and a 'parallel pregnancy and involution signature' during bovine mammary involution.

Prevalence and Trends in Donor Milk Use in the Well-Baby Nursery: A Survey of Northeast United States Birth Hospitals

BACKGROUND AND OBJECTIVES

Pasteurized donor human milk ("donor milk") is an alternative to formula for supplementation of breastfed infants. We conducted a survey to determine (1) prevalence, trends, and hospital-level correlates of donor milk use for healthy newborns in the northeast United States and (2) clinician knowledge and opinions regarding this practice.

METHODS

We conducted parallel surveys of clinicians (88% nurse and/or lactation consultant) at (1) all birth hospitals in Massachusetts (MA) and (2) all birth hospitals served by a northeast United States milk bank. We asked about hospital use of donor milk for newborns ≥35 weeks' gestation and receiving Level I care in well nursery, hospital-related factors we hypothesized would be associated with this practice, and clinician knowledge and opinions about donor milk use.

RESULTS

35/46 (76%) of MA birth hospitals and 51/69 (74%) of hospitals served by the milk bank responded; 71 unique hospitals were included. Twenty-nine percent of MA birth hospitals and 43% of hospitals served by the milk bank reported using donor milk for healthy newborns. Hospitals that used donor milk for healthy newborns had higher exclusive breastfeeding at hospital discharge than hospitals that did not (77% versus 56%, p = 0.02). Eighty-three percent of respondents agreed or strongly agreed that using donor milk is an effective way to increase the hospital's exclusive breastfeeding rate.

CONCLUSIONS

Many northeast United States birth hospitals currently use donor milk for healthy newborns. This practice is associated with higher exclusive breastfeeding at hospital discharge. Relationships with breastfeeding after discharge and related outcomes are unknown.

Donor Milk Utilization for Healthy Infants: Experience at a Single Academic Center

BACKGROUND

Banked donor milk (BDM) has historically been used as an alternative to formula for preterm infants. Recently, BDM has been endorsed by two national organizations for use in healthy infants. We sought to quantify utilization trends and characteristics of mothers and their healthy newborns who received BDM during their postpartum stay between 2013 and 2016 at a single academic medical center.

MATERIALS AND METHODS

In this observational study, we used a clinical log to identify all infants who received BDM in the well-baby nursery between July 2013 and June 2016. From this log, we abstracted data on the numbers of babies who received BDM, the quantity of BDM provided, and indications for usage. We also collected clinical data from the medical records of a subset of corresponding mothers and infants.

RESULTS

BDM utilization increased over time in healthy infants, with 0.04% of infants before July 2014 receiving BDM compared with 4.7% in July 2015 to June 2016. During the same periods, the number of bottles provided per infant also increased, from 0.6 bottles per infant to 4.6 bottles per infant. The most common indications for providing BDM were parent/caregiver request (19%) and excessive weight loss/dehydration (17%).

CONCLUSION

At our center, the use of BDM for healthy infants increased substantially over the study period. More research is urgently needed to understand the repercussions of this practice on resource utilization as well as short- and long-term breastfeeding and health outcomes.

Changes in milk composition associated with pethidine-PCEA usage after Caesarean section

The effect of pethidine as patient-controlled epidural analgesia (PCEA) on specific biochemical components in breast milk in relation to the timing of secretory activation is not well investigated. The aim of this study was to compare biochemical timing of secretory activation between women who had a vaginal (V) or Caesarean birth with pethidine-PCEA (CBP). Several milk samples were collected daily from 36 mothers (17 V, 19 CBP) for the first 265 h post-partum. Protein and lactose concentrations and Na+ and K+ ion levels were measured. Samples were assigned to three time periods: 0-72, >72-165 and >165-265 h post-partum for statistical analyses. Data were analyzed using linear mixed effect models. In the first 72 h post-partum, the mean difference in lactose concentration was 5 gL-1 higher in group V (P < 0.05). From >72-165 h post-partum, protein and Na+ concentrations were lower in group V (P = 0.05, P = 0.02), and K+ levels were higher in group V (P < 0.001). From >165-265 h post-partum, there were no significant differences between the groups. Biochemically, secretory activation had occurred by 72 h post-partum in both groups. There were greater variations in measured biochemical components observed within group CBP initially. However, by 165 h post-partum, there were no differences in the biochemical components between the groups. This suggests that effects of pethidine-PCEA are diminished by 72 h post-partum and undetected by 165 h.

Lactation and Management of Postpartum Disease

While much of the existing literature in the field of reproductive rheumatology focuses on fertility, preconception counseling, and pregnancy, there is limited information regarding the postpartum period and lactation. Evidence suggests that many rheumatologic disorders flare after delivery, which, along with limitations in medications compatible with breastfeeding, make this time period challenging for women with rheumatologic conditions. This article discusses rheumatologic disease activity during the postpartum period and reviews the safety during lactation of commonly used medications for the management of rheumatic diseases. Fortunately, many of the commonly used medications are compatible with breastfeeding.

After Chemotherapy Treatment for Maternal Cancer During Pregnancy, Is Breastfeeding Possible?

OBJECTIVE

To report breastfeeding complaints of women diagnosed with cancer during pregnancy and correlate success with characteristics of their treatment.

MATERIALS AND METHODS

This is a prospective cohort study of women diagnosed with cancer during pregnancy who attempted breastfeeding. We surveyed participants about breast engorgement, milk let down, and consistent breast milk production through mailed questionnaires. Treatment details, including the type and number of chemotherapy cycles given during pregnancy and antepartum or postpartum depression, were collected. A single pathologist evaluated surgical specimens to note lactational changes while blinded to patient's treatment. The primary endpoint was successful breastfeeding without reporting any lack of or decreased breast milk production.

RESULTS

When comparing women who underwent chemotherapy during pregnancy to women who did not, there was a significant difference in reporting a lack of or a perceived decrease in breast milk supply and the need to provide supplemental feeding to their infants (63.5% and 9%, respectively, p < 0.001). In the women who received chemotherapy, there was no significant difference in maternal age, cancer type, or stage with regard to breastfeeding difficulties. Gestational age at the first cycle and the number of cycles were significant factors associated with breastfeeding difficulties (p = 0.006 and p = 0.0003, respectively). Antepartum and postpartum depression was not associated with decreased breast milk production. A lack of lactational changes and significant lobular atrophy were noted in the women given neoadjuvant chemotherapy.

CONCLUSION

Women who undergo chemotherapy during a pregnancy are more likely to report breastfeeding difficulties.

Ultrasound findings of the physiological changes and most common breast diseases during pregnancy and lactation

Because of the physiological changes that occur during pregnancy and lactation, diagnostic ultrasound of the breast during these periods is a challenge for physicians. Therefore, a comprehensive understanding of imaging, anatomy, and physiology of the breast is important to effectively diagnosing diseases that can arise in women who are pregnancy or lactating. The aim of this article was to review the physiological changes that occur in the breasts during pregnancy and lactation, as well as to describe the main features of the breast diseases that occur most frequently during these periods.

Which breast pump for which mother: an evidence-based approach to individualizing breast pump technology

The majority of new mothers in the United States use breast pumps in the first 4 months postbirth in order to achieve their personal human milk feeding goals. Although these mothers seek guidance from health-care professionals with respect to the type and use of breast pumps, there are few evidence-based guidelines to guide this professional advice. This paper reviews the evidence to facilitate professional individualization of breast pump recommendations using three categories of literature: the infant as the gold standard to which the pump is compared; the degree of maternal breast pump dependency (for example, the extent to which the breast pump replaces the infant for milk removal and mammary gland stimulation); and the stage of lactation for which the pump replaces the infant. This review can also serve to inform public and private payers with respect to individualizing breast pump type to mother-infant dyad characteristics.

Relationships of Maternal Stress with Milk Immune Components in African American Mothers of Healthy Term Infants

BACKGROUND

In the United States, African American infants experience the highest mortality, and their mothers report the lowest breastfeeding rates. Science reports decreased infant mortality among breastfed infants and suggests that milk immune component (MIC) levels are associated with maternal stressors. Little is known about these relationships among African Americans; therefore the aim was to explore the relationships of African American mothers' stressors and MICs 1-14 days postdelivery.

MATERIALS AND METHODS

Mothers meeting eligibility requirements were approached for consent 48-72 hours postdelivery of a healthy term infant and given instructions to collect milk (Days 3, 9, and 14) and saliva (Day 9), as well as complete three Perceived Stress Scale questionnaires (Days 3, 9, and 14) and a survey of pregnancy stressors experiences. Pearson correlations and linear regressions were performed to assess the relationships of maternal stressors with MICs.

RESULTS

There was at least one statistically significant correlation of a maternal stressor with nine of the 10 MICs (effect sizes ranging from r = 0.22 to 0.38) on Days 3 and 9. Of all MICs, epidermal growth factor had the most associations with maternal stress indicators. No mediational relationship of cortisol with MICs was observed.

CONCLUSIONS

Many of the MIC changes observed could potentially impact the health of term and preterm infants. Further research is warranted.

Tissue-Specific Contributions of Paternally Expressed Gene 3 in Lactation and Maternal Care of Mus musculus

Paternally Expressed Gene 3 (Peg3) is an imprinted gene that controls milk letdown and maternal-caring behaviors. In this study, a conditional knockout allele has been developed in Mus musculus to further characterize these known functions of Peg3 in a tissue-specific manner. The mutant line was first crossed with a germline Cre. The progeny of this cross displayed growth retardation phenotypes. This is consistent with those seen in the previous mutant lines of Peg3, confirming the usefulness of the new mutant allele. The mutant line was subsequently crossed individually with MMTV- and Nkx2.1-Cre lines to test Peg3's roles in the mammary gland and hypothalamus, respectively. According to the results, the milk letdown process was impaired in the nursing females with the Peg3 mutation in the mammary gland, but not in the hypothalamus. This suggests that Peg3's roles in the milk letdown process are more critical in the mammary gland than in the hypothalamus. In contrast, one of the maternal-caring behaviors, nest-building, was interrupted in the females with the mutation in both MMTV- and Nkx2.1-driven lines. Overall, this is the first study to introduce a conditional knockout allele of Peg3 and to further dissect its contribution to mammalian reproduction in a tissue-specific manner.

[Breastfeeding: health benefits for child and mother]

The prevalence of breastfeeding in France is one of the lowest in Europe: 65% of infants born in France in 2010 were breastfed when leaving the maternity ward. Exclusive breastfeeding allows normal growth until at least 6 months of age, and can be prolonged until the age of 2 years or more, provided that complementary feeding is started after 6 months. Breast milk contains hormones, growth factors, cytokines, immunocompetent cells, etc., and has many biological properties. The composition of breast milk is influenced by gestational and postnatal age, as well as by the moment of the feed. Breastfeeding is associated with slightly enhanced performance on tests of cognitive development. Exclusive breastfeeding for at least 3 months is associated with a lower incidence and severity of diarrhoea, otitis media and respiratory infection. Exclusive breastfeeding for at least 4 months is associated with a lower incidence of allergic disease (asthma, atopic dermatitis) during the first 2 to 3 years of life in at-risk infants (infants with at least one first-degree relative presenting with allergy). Breastfeeding is also associated with a lower incidence of obesity during childhood and adolescence, as well as with a lower blood pressure and cholesterolemia in adulthood. However, no beneficial effect of breastfeeding on cardiovascular morbidity and mortality has been shown. Maternal infection with hepatitis B and C virus is not a contraindication to breastfeeding, as opposed to HIV infection and galactosemia. A supplementation with vitamin D and K is necessary in the breastfed infant. Very few medications contraindicate breastfeeding. Premature babies can be breastfed and/or receive mother's milk and/or bank milk, provided they receive energy, protein and mineral supplements. Return to prepregnancy weight is earlier in breastfeeding mothers during the 6 months following delivery. Breastfeeding is also associated with a decreased risk of breast and ovarian cancer in the premenopausal period, and of osteoporosis in the postmenopausal period.

Biomechanics of milk extraction during breast-feeding

How do infants extract milk during breast-feeding? We have resolved a century-long scientific controversy, whether it is sucking of the milk by subatmospheric pressure or mouthing of the nipple-areola complex to induce a peristaltic-like extraction mechanism. Breast-feeding is a dynamic process, which requires coupling between periodic motions of the infant's jaws, undulation of the tongue, and the breast milk ejection reflex. The physical mechanisms executed by the infant have been intriguing topics. We used an objective and dynamic analysis of ultrasound (US) movie clips acquired during breast-feeding to explore the tongue dynamic characteristics. Then, we developed a new 3D biophysical model of the breast and lactiferous tubes that enables the mimicking of dynamic characteristics observed in US imaging during breast-feeding, and thereby, exploration of the biomechanical aspects of breast-feeding. We have shown, for the first time to our knowledge, that latch-on to draw the nipple-areola complex into the infant mouth, as well as milk extraction during breast-feeding, require development of time-varying subatmospheric pressures within the infant's oral cavity. Analysis of the US movies clearly demonstrated that tongue motility during breast-feeding was fairly periodic. The anterior tongue, which is wedged between the nipple-areola complex and the lower lips, moves as a rigid body with the cycling motion of the mandible, while the posterior section of the tongue undulates in a pattern similar to a propagating peristaltic wave, which is essential for swallowing.

Cholera toxin enhances Na(+) absorption across MCF10A human mammary epithelia

Cellular mechanisms to account for the low Na(+) concentration in human milk are poorly defined. MCF10A cells, which were derived from human mammary epithelium and grown on permeable supports, exhibit amiloride- and benzamil-sensitive short-circuit current (Isc; a sensitive indicator of net ion transport), suggesting activity of the epithelial Na(+) channel ENaC. When cultured in the presence of cholera toxin (Ctx), MCF10A cells exhibit greater amiloride-sensitive Isc at all time points tested (2 h to 7 days), an effect that is not reduced with Ctx washout for 12 h. Amiloride-sensitive Isc remains elevated by Ctx in the presence of inhibitors for PKA (H-89, Rp-cAMP), PI3K (LY294002), and protein trafficking (brefeldin A). Additionally, the Ctx B subunit, alone, does not replicate these effects. RT-PCR and Western blot analyses indicate no significant increase in either the mRNA or protein expression for α-, β-, or, γ-ENaC subunits. Ctx increases the abundance of both β- and γ-ENaC in the apical membrane. Additionally, Ctx increases both phosphorylated and nonphosphorylated Nedd4-2 expression. These results demonstrate that human mammary epithelia express ENaC, which can account for the low Na(+) concentration in milk. Importantly, the results suggest that Ctx increases the expression but reduces the activity of the E3 ubiquitin ligase Nedd4-2, which would tend to reduce the ENaC retrieval and increase steady-state membrane residency. The results reveal a novel mechanism in human mammary gland epithelia by which Ctx regulates ENaC-mediated Na(+) transport, which may have inferences for epithelial ion transport regulation in other tissues throughout the body.

Management of breastfeeding during and after the maternity hospitalization for late preterm infants

Among infants born moderately and late preterm or early term, the greatest challenge for breastfeeding management is the late preterm infant (LPI) who is cared for with the mother in the maternity setting. Breastfeeding failure among LPIs and their mothers is high. Evidence-based strategies are needed to protect infant hydration and growth, and the maternal milk supply, until complete feeding at breast can be established. This article reviews the evidence for lactation and breastfeeding risks in LPIs and their mothers, and describes strategies for managing these immaturity-related feeding problems. Application to moderately and early preterm infants is made throughout.

Association between length of exclusive breastfeeding and subsequent breastfeeding continuation

BACKGROUND

Although breastfeeding initiation rates have improved, later prevalence is very low in the United Kingdom, and Northeast England is the region with the lowest rates.

OBJECTIVE

This study aimed to investigate novel in addition to well-established risk factors for cessation of breastfeeding among women in this region.

METHODS

Participants were 870 women considering breastfeeding prior to birth who were enrolled in the postnatal ward North East Cot trial at a tertiary hospital in Northeast England from 2008 to 2010. They provided weekly data on feeding and sleeping practices for 26 weeks postpartum using an automated telephone system with reminder postcards and contact by telephone, letter, or email if necessary. Cox proportional hazards regression was used to investigate factors associated with terminating any and exclusive breastfeeding in this period.

RESULTS

Ninety-four percent of women started any breastfeeding and 66% initiated exclusive breastfeeding. By 26 weeks postpartum, 47% were still breastfeeding, but < 1% were breastfeeding exclusively. Multivariate analysis showed that women who exclusively breastfed for at least 4 weeks breastfed for significantly longer after supplementation started (P < .001). Bed-sharing at home during the first 13 weeks was a significant predictor of both any and exclusive breastfeeding, as well as any breastfeeding after supplementation (P < .001). We also confirmed some recognized socio-demographic predictors of breastfeeding cessation in this location.

CONCLUSION

We found that exclusive breastfeeding for at least 4 weeks was significantly associated with longer breastfeeding continuation after supplementation, and bed-sharing at home was associated with longer breastfeeding regardless of the definition used.

Effect of mode of delivery on macronutrient content of breast milk

OBJECTIVE

To determine the effect of delivery type on macronutrient content of colostral milk.

MATERIALS AND METHODS

The study was conducted at Zekai Tahir Burak Maternity Teaching Hospital. Colostral milk samples from term lactating mothers who gave birth by vaginal or cesarean delivery (CD) were obtained on the 2nd postpartum day. Milk protein, fat, carbohydrate (CHO) and energy levels were measured by using a mid-infrared human milk analyzer.

RESULTS

A total of 204 term lactating mothers were recruited to the study; 111 mothers gave birth by vaginal route and 93 mothers by CD. Protein levels were statistically lower in colostral milk of mothers after CD compared to mothers who delivered vaginally (median 2.4 (range 0.3-6.4) g/dl versus 3 (0.5-6.3) g/dl, respectively; p = 0.036). Colostral fat, CHO and energy levels were similar between groups. In linear regression analysis, CD and maternal age were independently associated with lower protein content in colostrum.

CONCLUSION

Vaginal delivery is associated with higher colostrum protein content. Hormonal activity induced by labor pain and uterine contractions might account for the alterations in the protein composition of human milk to facilitate optimal development of important physiologic functions in newborns.

Dynamics of human milk nutrient composition of women from Singapore with a special focus on lipids

BACKGROUND

A recent report suggested that human milk (HM) composition not only changes with lactation stages but also vary according to gender of the offspring. In spite of available literature, the dynamic changes of HM composition still remain to be completely explored and characterized. Progress in analytical technologies together with quantitative sampling of HM allows for a better quantification of HM nutrients and thereby providing a deeper understanding of the dynamics of HM secretion.

OBJECTIVE

To characterize and quantify HM nutrients based on appropriate for analyses sampling procedures and advanced analytical methodologies.

CLINICAL STUDY DESIGN

We conducted an observatory, single center, longitudinal trial with HM collection at 30, 60, and 120 days postpartum from 50 mothers (singleton-deliveries of 25 male and 25 female infants). HM samples were analyzed for lipid, lactose, energy density, fatty acids, phospholipids, and gangliosides. Longitudinal analyses of the datasets have been carried out using linear mixed models.

RESULTS

HM for male infants compared to females at 120 days, were higher for energy content and lipids by 24 and 39%, respectively. Similarly, other bioactive lipids such as linoleic acid, phospholipids and gangliosides were also significantly different based on the gender of the infant. Significant stage-based differences were observed for total lipids, energy density, phospholipids, and gangliosides. Such difference in HM composition may stem from different energy needs to cope up for individual growth and development.

CONCLUSION

Collectively, the current observations affirm that HM secretion, especially the lipid composition, is a very dynamic and personalized biological process.