BACKGROUND: Concerns about reduced milk transfer with nipple shield (NS) use are based on evidence from studies with methodological flaws. Milk removal during breastfeeding can be impacted by infant and maternal factors other than NS use. The aim of this study was to control electric breast pump vacuum strength, pattern and duration across multiple study sessions to determine if NS use reduces milk removal from the breast.
METHODS: A within-subject study with two groups of breastfeeding mothers (infants < 6 months) were recruited; Control Group (CG): no breastfeeding difficulties; Pain Group (PG) used NS for persistent nipple pain. Mothers completed three randomised 15 min pumping sessions using the Symphony vacuum curve (Medela AG); no NS, fitted NS, and a small NS. Sessions were considered valid where the applied vacuum was within 20 mmHg of the set vacuum. Milk removal was considered as pumped milk volume, and also percentage of available milk removed (PAMR), which is calculated as the pumped volume divided by the estimated milk volume stored in the breast immediately prior to pumping.
RESULTS: Of 62 sessions (all: n = 31 paired sessions) a total of 11 paired sessions from both PG (n = 03) and CG (n = 08) were valid (subset) with and without a fitted NS. Only 2 small shield sessions were valid and so all small shield measurements were excluded. Both pumped volumes and PAMR were significantly lower with NS use for all data but not for subset data. (All: Volume and PAMR median: no NS: 76.5 mL, 69%, Fitted NS: 32.1 mL, 41% respectively (volume p = 0.002, PAMR p = 0.002); Subset: Volume and PAMR median: no NS: 83.8 mL, 72%; Fitted NS: 35.2 mL, 40% (volume p = 0.111 and PAMR p = 0.045). The difference in PAMR, but not volume, was statistically significant when analysed by linear mixed modelling. A decrease of 10 mmHg was associated with a 4.4% increase in PAMR (p = 0.017).
CONCLUSIONS: This experimental data suggests that nipple shield use may reduce milk removal. Close clinical monitoring of breastfeeding mothers using nipple shields is warranted.

Introduction: Dysphoric milk ejection reflex (D-MER) is emerging as a recognized phenomenon to describe an abrupt dysphoria, or undesirable feeling that occurs with the milk ejection reflex (MER) and then goes away after a few minutes. The purpose of this study was to determine the prevalence of D-MER among breastfeeding women and to describe the experience of symptoms associated with D-MER. Materials and Methods: To determine the prevalence of D-MER, a retrospective chart review was conducted over a 12-month period on women presenting for their 6- to 8-week postpartum visit. To describe the experience of D-MER, an anonymous cross-sectional survey consisting of 36 items was made accessible through a link to an online survey management platform. Participants were recruited through both paper and electronic posters at a variety of venues. Results: A prevalence rate of 9.1% was found. The respondents described similarities in their experiences with D-MER, to include feelings coming on suddenly and lasting for <5 minutes. The respondents described feeling anxious, sad, irritable, panicky, agitated, oversensitive, and tearful most often. Conclusion: This is the first study to quantify a prevalence rate and describe suspected experiences of D-MER. It provides the groundwork for future research to explore other contributing factors or relationships that may be relevant to D-MER. The findings support that the experience of D-MER is different from that of postpartum depression. Future research exploring the behavior of hormones and neurotransmitters within the context of lactation could contribute to the knowledge regarding D-MER.

Knowledge on the hemodynamics of the human lactating breast contributes to our understanding of lactation physiology, as well as the development and management of breastfeeding problems. The objective of this pilot study was to investigate whether laser Doppler perfusion monitoring (LDPM) can be employed to measure physiological changes in mammary cutaneous perfusion during milk extraction.
We evaluated mammary cutaneous perfusion with LDPM in nine lactating women during milk extraction in both the ipsilateral (\'milk extracting\') and contralateral (\'passive\') breast. Fourier domain filtering of the LDPM signal was applied to correct for the influence of the periodic tissue movement caused by the breast pump.
Cutaneous perfusion increased temporary during 23.7  ±  18.9 s by 18%-74% for all women who sensed their milk ejection reflex (n  =  6) in both the ipsilateral and contralateral breast. For those women who did not sense a milk ejection reflex (n  =  3), the changes in cutaneous perfusion were less outspoken (maximally 26%).
This pilot study provides new insights into mammary hemodynamics and demonstrates that LDPM is a promising method for the further investigation of physiological changes in mammary cutaneous perfusion during milk ejection. Objective feedback on the occurrence and progression of milk ejection can support lactation research in general, maternal breastfeeding confidence, and may be an early indicator for the development of breastfeeding problems.

BACKGROUND: The purpose of this study was to identify potential predisposing factors associated with human infectious mastitis.
METHODS: We conducted a case-control study among breastfeeding women, with 368 cases (women with mastitis) and 148 controls. Data were collected by a questionnaire designed to obtain retrospective information about several factors related to medical history of mother and infant, different aspects of pregnancy, delivery and postpartum, and breastfeeding practices that could be involved in mastitis. Bivariate analyses and multivariate logistic regression model were used to examine the relationship between mastitis and these factors.
RESULTS: The variables significantly- and independently-associated with mastitis were cracked nipples (P < 0.0001), oral antibiotics during breastfeeding (P < 0.0001), breast pumps (P < 0.0001), topical antifungal medication during breastfeeding (P = 0.0009), mastitis in previous lactations (P = 0.0014), breast milk coming in later than 24 h postpartum (P = 0.0016), history of mastitis in the family (P = 0.0028), mother-infant separation longer than 24 h (P = 0.0027), cream on nipples (P = 0.0228) and throat infection (P = 0.0224).
CONCLUSIONS: Valuable factors related to an increased risk of infectious mastitis have been identified. This knowledge will allow practitioners to provide appropriate management advice about modifiable risk factors, such as the use of pumps or inappropriate medication. They also could identify before delivery those women at an increased risk of developing mastitis, such as those having a familial history of mastitis, and thus develop strategies to prevent this condition.

OBJECTIVE: To compare the effects of metoclopramide and domperidone on the breast milk output of mothers with infants in neonatal intensive care.
METHODS: Double-blind randomised controlled trial.
METHODS: Tertiary level neonatal intensive care unit (NICU).
METHODS: Eighty mothers expressing breast milk for their infants (mean gestational age 28 weeks) based in NICU and the amounts expressed fell short of the prescribed target.
METHODS: Mothers were randomised to receive domperidone or metoclopramide for 10 days (10 mg three times a day).
METHODS: Total milk volume daily for up to 10 days before the medication, 10 days during the trial and up to 10 days after medication. Adverse side effects were also recorded.
RESULTS: Mothers produced more milk in the domperidone group and achieved a mean of 96.3% increase in milk volume (mean increase/pretrial volume) compared with a 93.7% increase for metoclopramide. After adjusting for the amount of milk produced prior to medication, the mean amount of milk produced while taking medication for those on domperidone was 31.0 ml/24 h (95% CI -5.67 to 67.6) greater than the mean for those on metoclopramide. Seven mothers taking metoclopramide reported side effects and three taking domperidone; a further eight women (of 29) who had a follow-on prescription for metoclopramide also reported side effects.
CONCLUSIONS: Oral domperidone and metoclopramide increased the volume of milk produced by mothers who are expressing to feed their babies in NICU. There were small differences in milk output between the two medications and in the incidence of side effects, but the differences were non-significant.

There is an increasing trend in Australia and elsewhere for mothers to express breast milk. The purpose of this study was to explore breastfeeding women\'s experiences of expressing breast milk. An anonymous online questionnaire was sent to Victorian members of the Australian Breastfeeding Association via an e-mail link. Response fraction was 903 of 3024 (29.9%). The most common reason for expressing milk was to \"store extra breast milk\" (57%, 479/836). The most important reason was \"not enough milk\"/\"to make more milk\" (15%, 118/771). The majority of women (65%, 666/843) used an electric breast pump, and this method of expressing was preferred by 59% (454/769) of women. Adverse effects of pumps were pain (17%, 126/737) and damage to nipples (11%, 86/737). Breast pumps may have a role in enabling women to extend the duration of breast milk feeding, but further research is needed.

A questionnaire was sent to 2099 dairy farms to investigate the occurrence of poor milkability. Based on that, the frequency of poor milkability in Swiss dairy cows was 4% and the percentage of cows treated with oxytocin (OT) was 2%. In addition, 270 dairy farms that had reported cases of animals with poor milkability were contacted for an interview to classify the disorders. Farmers suspected disturbed milk ejection in 52%, anatomical dysfunction of the teat and/or the udder in 16% and milk ejection disorder or impaired milkability caused by discernable environmental factors in 32% of the cases. Forty-eight animals from 18 farms with suspected milk ejection disorders were selected for an experimental field study which included milk flow recording and OT administration to induce milk ejection. After cessation of the spontaneous milk flow, a low dose of OT (0.2, 0.5 or 1 i.u.) was injected i.v. to test the responsiveness of the udder to OT at a physiological level. When milk flow ceased again, 10 i.u. OT was injected i.v. (supraphysiological) to ensure complete udder emptying and to determine the residual milk. Milk ejection disorder could be confirmed in 69% of the cases, i.e. if residual milk was >20% of the total milk. Because in 27% of the animals milk ejection disorder was not confirmed on the basis of elevated residual milk, an anatomical disorder of the teat and/or the udder was suspected. Milk ejection disorder could be confirmed in 69% of the cases whereas in 27% of the suspected cases an anatomical disorder of the teat and/or the udder was suspected. An increased cortisol production in cows with milk ejection disorder was not obvious because faecal concentrations of cortisol metabolites with a 5 beta-androstane-3 alpha,11 oxo-structure were not augmented in animals with disturbed milk ejection.

The present study is an attempt to reveal the spinal and supraspinal organization of the ascending branch of the milk-ejection reflex in the ewe by means of a tract-tracing technique. For this purpose, injections of horseradish peroxidase (HRP) were performed into the lateral cervical nucleus (LCN) and into the hypothalamic paraventricular nucleus (PVN). Peroxidase injections into the LCN revealed retrogradely labelled neurons in the medial part of laminae I-III of the ipsilateral L3 and L4 spinal segments, while injections of HRP into the PVN revealed retrogradely labelled cells in the contralateral LCN and the medial cuneate nucleus. Taking into account the results obtained, it is concluded that the transmission of the afferent input from the nipples to the PVN is accomplished by at least two pathways: one employing a single relay station located in the medial cuneate nucleus, and another possessing two relay stations located in the medial part of laminae I-III of the dorsal horn of L3 and L4 spinal segments and in the LCN.

BACKGROUND: Human milk has considerable short and long term benefits for preterm infants, but mothers may experience difficulties in expressing breast milk for infants too immature or sick to breast feed. Oxytocin has been used to assist breast feeding and milk expression, but few data are available to support this intervention in the neonatal unit setting.
OBJECTIVE: To test the hypothesis that oxytocin nasal spray increases early milk output in mothers expressing milk for preterm infants.
METHODS: A randomised, double blind trial of oxytocin nasal spray (100 microl per dose) versus placebo was conducted in mothers delivering infants <35 weeks gestation. Sprays were used before expression of milk using an electric pump up to day 5.
RESULTS: Total weight of milk expressed while using spray (study powered to detect >1SD difference between groups).
RESULTS: Pattern of milk production; number of pumping sessions; weight/fat content of milk expressed during a fixed 20 minute period on day 5 (\"physiological study\"); mother\'s opinion of expressing and spray assessed by questionnaire.
RESULTS: Fifty one mothers were randomised (27 oxytocin, 24 placebo). Total milk production did not differ between groups. Repeated measures analysis of variance suggested significantly (p = 0.001) different patterns of milk production, with initial faster production in the oxytocin group then convergence between groups. Parity did not influence the response to the intervention. No significant differences were seen in milk weight or fat content in the physiological study nor in mothers\' opinions of milk expression and treatment.
CONCLUSIONS: Despite marginal differences in the pattern of early milk production, the use of oxytocin nasal spray did not significantly improve outcome. Most mothers believed they were receiving the active spray, suggesting a significant placebo effect (supported by limited data from historical controls) and benefits from the extra breast feeding support available during the study.

The purpose of this cross-fostering study was to investigate neonatal survival following exposure of pregnant rats to atosiban (1-deamino-2-D-Tyr(OEt)-4-Thr-8-Orn-oxytocin), an oxytocin antagonist. Atosiban was administered subcutaneously from days 15 to 20 of gestation at 300 mg/kg/day, and controls received vehicle alone. Parturition was observed at 30 min intervals throughout the period that births were occurring. There was no effect of treatment on number of pups born or neonatal viability. Within 1 h of birth, litter size was standardised to five males and five females, followed immediately by cross-fostering either between or within groups. Offspring from treated mothers reared by control mothers had normal survival and weight gain. There was poor survival and weight gain in offspring from control mothers reared by treated mothers. There was clear evidence that lactation was impaired in the treated females, leading to the conclusion that poor neonatal survival in offspring reared by treated mothers was attributable to a failure of milk let-down.