Journal of Human Lactation

In 2019, 14.0% of infants in Thailand were exclusively breastfed up to 6 months of age. To increase exclusive breastfeeding, an objective assessment measure would be useful to maternity care providers for appraising the problems encountered by new mothers’ experiences with breastfeeding.

To translate the Bristol Breastfeeding Assessment Tool from English into Thai; to assess the reliability and validity of the Thai Bristol Breastfeeding Assessment Tool; and to explore the relationship of a mother’s self-efficacy to successful breastfeeding.

Using a methodological design, we purposively sampled 302 new mothers from two tertiary hospitals in Thailand who had given birth to a single baby with an uncomplicated vaginal birth. The Thai Bristol Breastfeeding Assessment Tool’s structure was examined using confirmatory factor analysis. Concurrent and convergent validity were assessed using the Thai LATCH instrument and Thai Breastfeeding Self-Efficacy Scale, respectively.

The inter-item Thai Bristol Breastfeeding Assessment Tool correlation coefficients were positive and strong. The correlation between scores of the Thai Bristol Breastfeeding Assessment Tool and Thai LATCH instrument were positive and strong and had acceptable concurrent validity. The confirmatory factor analysis model fit the Thai Bristol Breastfeeding Assessment Tool data perfectly and the Cronbach’s alpha coefficient had acceptable internal reliability.

The Thai Bristol Breastfeeding Assessment Tool is a cross-culturally translated instrument equivalent to its English version and demonstrated acceptable validity and reliability. The instrument provides a mechanism for an objective assessment and monitoring system of optimal breastfeeding practices in Thai mothers with newborns.

Identifying those at risk for suboptimal breastfeeding outcomes remains critical for improving maternal and child health. Prenatal breastfeeding motivation may be a key predictor useful for identifying those who would benefit from additional breastfeeding support.

To (1) validate a breastfeeding-specific adaptation of the Treatment Self-Regulation Questionnaire (TSRQ-BF); and (2) determine if breastfeeding motivation predicts prenatal breastfeeding intentions and early breastfeeding outcomes.

Participants in their third trimester of pregnancy (N = 150) completed several instruments, including the TSRQ-BF and infant feeding intention, and could opt to participate in an assessment of early breastfeeding outcomes (by medical record review). TSRQ-BF subscales were derived from factor analysis, and multivariable regression was used to evaluate the association between TSRQ-BF subscale scores and breastfeeding intention and outcomes during the birth hospitalization.

Autonomous (related to personal values/beliefs regarding self) and Autonomous-Baby (values/benefits for the infant) subscale scores were positively associated with intended exclusivity (aOR [95% CI]: 2.22 [1.57, 3.30], 4.94 [2.49, 11.07], respectively) while higher scores on these subscales predicted longer time to planned cessation (aHR [95% CI]: 0.72 [0.61, 0.84],0.52 [0.34, 0.81]). Higher Amotivation (lack of motivation) scores were negatively associated with intended exclusivity (0.45 [0.26, 0.74]). Higher scores on Autonomous, Autonomous-Baby, and Controlled (avoidance of negative feelings/punishment or gaining reward) subscales were associated with greater odds of hospital exclusivity (aOR [95% CI]: 3.39 [1.75, 8.00], 3.44 [1.66, 9.04] and 6.05 [1.88, 29.04]) and lower odds of 2-day formula supplementation (aOR [95% CI]: 0.31 [0.14, 0.59],0.28 [0.11, 0.59], 0.19 [0.04, 0.62]).

The TSRQ-BF predicted breastfeeding intent and outcomes, and may be helpful for identifying patients at risk for suboptimal breastfeeding outcomes before delivery.

Remdesivir was originally developed to treat Ebola hemorrhagic fever, and its efficacy in treating coronavirus disease 2019 was detected during a preliminary analysis of a randomized controlled trial. It is known that Severe Acute Respiratory Syndrome Coronavirus 2 is not transmitted through human milk, but data about the presence of remdesivir in human milk have been lacking.

In this case study, we determined the human milk-to-serum drug concentration ratio and the relative dose of Remdesivir in one participant.

The participant, a 28-year-old primipara, was found to have Coronavirus 2 infection in 2019, 2 days after delivery. She was given Remdesivir. The Remdesivir concentration in maternal serum and human milk was measured, and the milk-to-serum drug concentration ratio was found to be low (0.089), as was the relative infant dose (0.0070). The participant could not breastfeed her infant during her Coronavirus 2 infection treatment because in Japan anyone with COVID-19 was completely quarantined. However, she was able to resume breastfeeding after discharge and breastfed her infant for 6 months with supplements.

Given the low amount of Remdesivir in the participant’s milk, the inclusion of antibodies to Severe Acute Respiratory Syndrome Coronavirus 2, which can be expected to protect the infant from infection, and various other benefits of human milk, suggests that breastfeeding is safe during treatment with Remdesivir.

Developing a simple quantitative tool for mastitis diagnosis is essential. The Ion-Selective Electrode for sodium has been reported to reliably measure sodium concentrations in human milk.

To determine whether an Ion-Selective Electrode measurement of sodium:potassium ratios could serve as a diagnostic tool for mastitis and, if so, to determine the diagnostic cut-off value.

A total of 107 milk samples, including 55 from milk bank donors and 52 from participants with mastitis, were studied. The sodium:potassium ratios were determined in 33 samples (without mastitis n = 15; with mastitis n = 18) by the Ion-Selective Electrode and ion chromatography. The remaining 74 samples (donor milk n = 40; participants with mastitis n = 34) were analyzed by Ion-Selective Electrode only. Values were averaged over three measurements for each method.

The median postpartum months of donors and participants with mastitis were 2 and 3 months, respectively. The mean (SD) sodium:potassium ratios without and with mastitis were 0.5 (0.1) and 1.7 (1.2), respectively. A positive correlation existed between sodium:potassium ratios obtained from the two methods (r = 0.98). Area under the curve values were 0.951 (95% CI [0.904, 0.986]) for the Ion-Selective Electrode (N = 107) and 0.978 (95% CI [0.926, 1.000]) for the ion chromatography (n = 33) methods. The optimal cut-off value for the Ion-Selective Electrode method was 0.60, with 86.5% sensitivity and 92.7% specificity.

The Ion-Selective Electrode was sufficiently accurate for the diagnosis of mastitis. Cohort studies are needed to explore the relationship between sodium:potassium ratios and clinical outcomes.

Previous research examined effects of human milk on the infant gut microbiota, but little attention has been given to the microbiota of lactating women.

To determine associations between exclusive human milk feeding and gut microbiota characteristics in mothers and infants at 6-weeks postpartum.

A sample of mother–infant dyads (N = 24) provided fecal samples and questionnaire responses at 6-weeks postpartum as part of the Pregnancy, EAting & POstpartum Diapers study. Deoxyribonucleic acid was extracted from stool samples, followed by (V4) 16S ribosomal ribonucleic acid gene amplicon sequencing. Alpha and beta diversity, in addition to taxa differences, were compared by human milk exposure status, exclusive versus non-exclusive. A subset of dyads (those exclusively fed human milk; n = 14) was analyzed for shared bifidobacterial species using polymerase chain reaction.

Alpha diversity was significantly lower in exclusively human milk-fed infants. Maternal lactation status (exclusive vs. partial) and Shannon diversity were associated in univariate analysis but were no longer associated in multivariable regression including body mass index category in the model. Beta diversity (Sorensen dissimilarity) of fecal samples from women and infants was significantly associated with human milk feeding. Of six infants with Bifidobacterium longum subspecies longum in their fecal samples, all their mothers shared the same species.

Maternal gut microbiotas differ by lactation status, a relationship potentially confounded by body mass index category. Further research is needed to identify whether lactation directly influences the maternal gut microbiota, which may be another mechanism by which lactation influences health.

Medicalized Ketogenic Therapy is commonly used to treat refractory epilepsy. Patients have varying degrees of seizure or symptom relief, responding at individual levels of ketone production. Typically, initiating the therapy necessitates the discontinuation of breastfeeding. Our case study mother was keen to continue breastfeeding if possible. We were able to achieve this by placing the healthy mother on a ketogenic diet and altering the composition of the mother’s own milk.

Pediatric Medicalized Ketogenic Therapy is delivered through a ketogenic diet consisting of up to 90% fat, measuring of ingredients to 0.1 g matching a food prescription of fat, protein, and carbohydrate. We placed the mother on a less stringent ketogenic diet achieving 61% fat and measured both infant and mother’s blood sugar levels and ketones. The hypothesis was that changes would occur in the mother’s own milk fat content, and/or ketones would be passed directly to the infant. If therapeutic levels of ketones were reached in the infant and a reduction in seizures observed, breastfeeding could continue.

Over 3 months we achieved a calorific increase of the mother’s mature milk by an additional 134%. The infant was successfully put into nutritional ketosis and visible seizures eliminated.

Medicalized Ketogenic Therapy can be safely used to treat seizures of breastfeeding infants diagnosed with epilepsy, through management of the mother on a ketogenic diet. Significantly increasing the mature mothers own milk fat component could have implications for other areas, including faltering growth.

Efforts to provide accessible and effective infant feeding support are advancing to set up new families to meeting their goals. However, data continue to be limited for understanding how inpatient postpartum support and experiences contribute to exclusive breastfeeding during hospitalization.

To explore postnatal unit experiences including skin-to-skin contact, overnight support, rooming-in, responsive clinicians, and understandable communication that correlate with early infant feeding outcomes among a sample of mothers who intended to breastfeed.

This was a prospective cross-sectional survey study. Through secure online survey, participants submitted (N = 2,401) responses from November 2016 to May 2017 about their experiences with maternity healthcare and offered thoughts on the postnatal unit environment. Descriptive statistics were used to examine distributions of maternal characteristics, postpartum experience, and birthing facility characteristics.

Exclusive breastfeeding was positively correlated with the following postnatal unit experiences: mother did not ask that her infant be taken out of the postnatal unit room; infant staying in postnatal unit room except for treatment(s); mother got help from clinical staff when needed after pressing the call button; and nurse, midwife, and/or doctor always explained information to mother in ways that they understood.

Postnatal unit experiences associated with exclusive breastfeeding during postpartum hospitalization were rooming in; parents who did not ask for their infant to be taken out of the unit room; whether mothers received timely help from clinical staff; and information was explained in a way they could understand.

The retention of human milk nutrients in gastric tubes used to feed premature infants is a challenge to be overcome.

To evaluate (1) the performance of six homogenizers (mixing processor, piston valve, ultrasonic bath, ultraturrax, stirring mixer, and ultrasound probe) for the fat retention reduction in gastric tubes; (2) the influence of the best homogenization conditions on the fatty acid and protein profiles of human milk; and (3) the cost/benefit ratio for the inclusion of homogenization as a new step in human milk processing.

The influence of different levels and times of homogenization on reducing fat retention of human milk in probes was evaluated in this comparative prospective cross-sectional study. After homogenization, human milk flowed through a gavage and infusion pump apparatus used for feeding. Fat content was quantified before and after feeding. The techniques that reduced fat globule sizes and/or promoted a lower percentage of fat holding were evaluated for efficiency, variations in the fatty acid and protein profiles, and energy density and operating costs.

Homogenization led to a reduction in fat retention in feeding probes. The mixer processor and the ultrasound probe reduced fat retention by 99.23% (SD = 0.07) and 99.95% (SD = 0.02), respectively, and did not negatively influence fatty acid and protein profiles. The mixer processor demonstrated low energy density and low cost for human milk processing.

Homogenization promoted reduced fat retention in the feed probe and could help maintain fat nutrients of human milk during enteral feeding.

Microwave heating can be effective in preventing cytomegalovirus infection transmitted via human milk. Temperature changes during microwaving using different containers, in different areas inside a container, or using milk from different mothers are not well studied.

To determine temperature changes of human milk during microwaving using different containers, in different container areas, using different human milk, and in a 30-ml soft polypropylene bag (sachet) immersed in water.

In this experimental in vitro study, human milk (100 ml) was poured into six different bottles. The temperature was monitored simultaneously at each bottle’s bottom and surface (microwaving at 600 W) and at nine places inside the container (microwaving at 500 W). Human milk (20 ml) from six participants was inserted into a sachet, then immersed in 80 ml of human milk or water in a bottle, and the temperatures inside and outside the sachet during microwaving (at 500 W) were monitored.

The temperature changes at the surface were significantly larger than those at the bottom. Temperatures at the bottoms of different bottles, of human milk from different participants, or inside and outside the sachet, did not differ significantly. No temperature outliers inside the bottle were observed.

Microwaving at 500 W and 600 W for 60 s was not significantly different in temperature changes among different areas inside bottles or among milk from different participants. A small volume of human milk (up to 100 mL) can be heated using a sachet.

Transgender and gender diverse individuals may choose to provide their infants with human milk. Lactating transgender men may experience gender dysphoria and desire to initiate or reinitiate gender-affirming testosterone therapy. However, there is limited safety data regarding use of testosterone during lactation.

A 30-year-old G2P2 transgender man with gender dysphoria sought to initiate gender-affirming testosterone therapy while lactating.

Subcutaneous testosterone was self-administered beginning at 13 months post-partum. We prospectively collected data on circulating testosterone concentrations in parent serum, milk, and infant serum over 5 months until the infant self-weaned. The infant was monitored for growth and development at routine pediatric outpatient appointments. Parent serum testosterone concentrations rose with the initiation of testosterone therapy, reaching therapeutic concentrations by Day 14. Milk testosterone concentrations also increased with a maximum concentration of 35.9 ng/dl when the lactating parent was on a dose of 80 mg subcutaneous testosterone cypionate weekly. The calculated milk/plasma ratio remained under 1.0 and the calculated relative infant dose remained under 1%. The infant had no observable side effects, and his serum testosterone concentrations remained undetectable throughout the study period.

This is the first study with data regarding human milk and infant serum testosterone concentrations during the initiation of gender-affirming testosterone therapy in a lactating individual. This evidence can help families and clinicians with decisions regarding lactation and testosterone use.

Social norms and public perception of breastfeeding are well-established predictors of breastfeeding outcomes; however, little is known about perceptions of breastfeeding beyond infancy or public breastfeeding among the public in Nova Scotia, Canada.

To explore public opinion about breastfeeding beyond infancy and public breastfeeding.

In this cross-sectional study participants were recruited from public spaces in Nova Scotia, Canada. Using photo elicitation methods, participants (N = 229) viewed six photographs of breastfeeding children aged 2 weeks, 13 months, and 2.5 years, one photograph captured at home, and the other in a public space (a café, a store, or outdoors). Participants were asked to score their self-rated comfort with each photograph on a 10.0 cm visual analog scale and asked to share their feelings about each photograph (open-ended responses).

Mean (SD) visual analog scale comfort scores for photographs differed by location (private, 7.9 [2.2]; public, 7.3 [2.6]; p < .05) and child age (2 weeks, 8.5 [2.0]; 13 months, 7.5 [2.6]; 2.5 years, 6.9 [3.0]; p < .05). Participants who identified as women and parents self-reported significantly higher comfort with all photographs, while younger participants and urban dwellers were generally less comfortable. Open-ended responses varied considerably, but a higher proportion of negative comments were reported for older children feeding in public spaces (e.g., 2.5-year-old in public: “Inappropriate. Indecent. Abnormal.”).

Given the importance of social norms in supporting breastfeeding, future public health campaigns should strive to normalize breastfeeding beyond infancy, and in public spaces.