Randomized study comparing the efficacy of a novel manual breast pump with a mini-electric breast pump in mothers of term infants

Investigation of the Effect of Human Milk Expression Techniques on Milk Content: A Systematic Review

BACKGROUND

If the mother and infant cannot meet after birth, it is recommended to express milk and give it to the infant. There was evidence indicating that there might be decrease in essential nutrient values in human milk content depending on the expression technique in literature. The goal of this systematic review was to investigate the effect of human milk expression techniques on the macronutrient milk content and establish an evidence base for future studies.

METHODS

Studies investigating the effect of human milk expression techniques on milk content were reviewed without year limitations. A literature review was conducted in six electronic databases (MEDLINE, Web of Science, PubMed, ScienceDirect, CINAHL and Cochrane) until 30 May 2021, using the keywords of breast milk expression techniques, milk content and breast milk pumping.

RESULTS

From 258 articles initially screened, we included 6 articles in the systematic review. The fat, protein and lactose content of human milk was analyzed in the studies reviewed. It was concluded that there was no significant effect on the protein (9.7-9.8 g/dl and 2.1-2.1 g/dl, respectively) and lactose (6.50-6.53% and 6.1-6.1 g/dl, respectively) content of milk. However, the fat (58.30, 48.81g/l; 2.6-2.2 g/dl) content was affected.

CONCLUSIONS

This study investigated the effect of milk expression techniques on the macronutrient content of human milk, and it was concluded that there was no significant effect on the protein and carbohydrate content of milk. However, the fat content was affected. Limitation of this study is that some factors that might affect the content of human milk were not standardized sufficiently in the included studies.

Measuring Mothers' Viewpoints of Breast Pump Usage

Breastfeeding has short- and long-term positive influences on the health and wellbeing of the child. There are situations where breastfeeding does not occur and expressed or pumped mother's milk is used. Mothers and healthcare providers report problems or negative views on using pumps in studies across the globe. This systematic review and secondary analysis of 18 random control trials related to mothers' views of breast pumps examines the range of viewpoints gathered, the variety of measurement instruments used, how the outcomes are reported and the challenges that occur. It aims to inform critical reading of research as well as future research design. Devices which the mother views as comfortable and useful will facilitate more infants to receive human milk when direct breastfeeding does not occur, and they will have a positive influence on health and wellbeing.

Short-term efficacy of two breast pumps and impact on breastfeeding outcomes at 6 months in exclusively breastfeeding mothers: A randomised trial

The provision of breast pumps is a potential strategy to increase breastfeeding duration. This trial compared the effectiveness and acceptability of two breast pumps in mothers exclusively breastfeeding (EBF) their healthy term infant. It also tested whether provision of pumps versus vouchers of equivalent value influenced breastfeeding or attainment of mothers' goals at 3 and 6 months. Mothers were randomised at 3- to 4-week post-partum (Beijing [n = 30], Moscow [n = 34], London [n = 45], New York [n = 3]) to groups A (Philips single-electric pump, Natural bottle), B (Medela Swing single-electric pump, Calma bottle), or C (Control; vouchers). At 6 weeks, group A and B mothers expressed for 10 min/breast; milk weight and opinions of pump/bottle were recorded. Feeding practices were assessed using questionnaires at 3 and 6 months. Milk weight/flow pattern did not differ between groups. Pump A scored significantly better for ease-of-use, cushion-feel, need-to-lean-forward, pleasant, comfort. At 3 and 6 months, %EBF or meeting their goal was not significantly different; (3 months: 86%, 85%, 84%; 6 months: 20%, 15%, 26%; meeting goal 24%, 17%, 27% for A, B, and C). Expressed breast milk (EBM) provision was higher in groups A and B (3 months: 76%, 76%, 24% (p < 0.001); 6 months: 83%, 87%, 32% (p < 0.001); and negatively predicted EBF at 6 months (OR no EBM 5.07, 95% CI [1.56, 16.5]). The pumps were equally effective for milk expression at 6 weeks. Pump provision did not significantly influence breastfeeding practices or attainment of goals but resulted in higher EBM provision, which was associated with lower EBF but not other breastfeeding categories at 6 months.

Predictors of expressed breast milk volume in mothers expressing milk for their preterm infant

BACKGROUND

An understanding of predictors of breast milk production may enable the provision of better advice and support to mothers with preterm infants who may need to express milk for long periods.

OBJECTIVE

To investigate factors predicting the amount of milk expressed by mothers for their preterm infant (1) during the first 10 days and (2) during the infant's whole hospital stay.

METHODS

62 mothers with preterm infants <34 weeks who participated in a randomised trial comparing two breast pumps completed 10-day diaries including weight of milk expressed and questionnaires giving their opinion of the breast pump; 47 mothers provided data on milk expression up to the infant's hospital discharge.

RESULTS

Significant predictors of 10-day milk weight in multivariate models were the number of episodes of 'breast feeding' (17 g (95% CI 8 to 26, p=0.001) increase per episode), the use of double versus single pumping (109 (31-186, p=0.007) g/day more) and the number of complete daily records (17 (1-33, p=0.04) g increase/day). Significant multivariate predictors of total milk production were double versus single pumping (491 (55) mL/day vs 266 (44) mL/day), expressing 500 mL/day by day 10 (525 (53) mL/day vs 232 (43) mL/day) and a higher score for breast pump 'comfort' (best=489 (39) mL/day, middle=335 (57) mL/day, worst=311 (78) mL/day).

CONCLUSIONS

These results suggest that relatively simple, modifiable factors can favourably impact milk production in the neonatal intensive care unit setting and emphasise the importance of double pumping, early establishment of milk production and design features of the breast pump that promote comfort.

TRIAL REGISTRATION NUMBER

NCT00887991.

Methods of milk expression for lactating women

BACKGROUND

Breastfeeding is important, however not all infants can feed at the breast and methods of expressing milk need evaluation.

OBJECTIVES

To assess acceptability, effectiveness, safety, effect on milk composition, contamination and costs of methods of milk expression.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (21 March 2016), handsearched relevant journals and conference proceedings, and contacted experts in the field to seek additional published or unpublished studies. We also examined reference lists of all relevant retrieved papers.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing methods at any time after birth.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.

MAIN RESULTS

This updated review includes 41 trials involving 2293 participants, with 22 trials involving 1339 participants contributing data for analysis. Twenty-six of the trials referred to mothers of infants in neonatal units (n = 1547) and 14 to mothers of healthy infants at home (n = 730), with one trial containing mothers of both neonatal and healthy older infants (n = 16). Eleven trials compared one or more types of pump versus hand expression and 14 studies compared one type of pump versus another type of pump, with three of these studies comparing both hand expression and pump types. Twenty studies compared a specific protocol or adjunct behaviour including sequential versus simultaneous pumping protocols, pumping frequency, provision of an education and support intervention, relaxation, breast massage, combining hand expression with pumping and a breast cleansing protocol.Due to heterogeneity in participants, interventions, and outcomes measured or reported, we were unable to pool findings for most of the specified outcomes. It was not possible therefore to produce a 'Summary of findings' table in this update. Most of the included results were derived from single studies. Trials took place in 14 countries under a variety of circumstances and were published from 1982 to 2015. Sixteen of the 30 trials that evaluated pumps or products had support from the manufacturers. The risk of bias of the included studies was variable. Primary outcomesOnly one of the 17 studies examining maternal satisfaction/acceptability with the method or adjunct behaviour provided data suitable for analysis. In this study, self-efficacy was assessed by asking mothers if they agreed or disagreed with the following statement: 'I don't want anyone to see me (hand expressing/pumping)'. The study found that mothers who were using the electric pump were more likely to agree with the statement compared to mothers hand expressing, (mean difference (MD) 0.70, 95% confidence interval (CI) 0.15 to 1.25; P = 0.01, participants = 68). Mothers who were hand expressing reported that the instructions for expression were clearer compared to the electric pump, (MD -0.40, 95% CI -0.75 to -0.05; P = 0.02, participants = 68). Descriptive reporting of satisfaction in the other studies varied in the measures used, did not indicate a clear preference for one pump type, although there was satisfaction with some relaxation and support interventions.We found no clinically significant differences between methods related to contamination of the milk that compared any type of pump to hand expression (risk ratio (RR) 1.13, 95% CI 0.79 to 1.61; P = 0.51, participants = 28), manual pump compared to hand expression, (MD 0.20, 95% CI -0.18 to 0.58; P = 0.30, participants = 142) a large electric pump compared to hand expression (MD 0.10, 95% CI -0.29 to 0.49; P = 0.61, participants = 123), or a large electric pump compared to a manual pump (MD -0.10, 95% CI -0.46 to 0.26; P = 0.59, participants = 141).The level of maternal breast or nipple pain or damage was similar in comparisons of a large electric pump to hand expression (MD 0.02, 95% CI -0.67 to 0.71; P = 0.96, participants = 68). A study comparing a manual and large electric pump, reported sore nipples in 7% for both groups and engorgement in 4% using a manual pump versus 6% using an electric pump; and in one study no nipple damage was reported in the hand-expression group, and one case of nipple damage in each of the manual pump and the large electric pump groups.One study examined adverse effects on infants, however as the infants did not all receive their mothers' expressed milk, we have not included the results. Secondary outcomesThe quantity of expressed milk obtained was increased, in some studies by a clinically significant amount, in interventions involving relaxation, music, warmth, massage, initiation of pumping, increased frequency of pumping and suitable breast shield size. Support programmes and simultaneous compared to sequential pumping did not show a difference in milk obtained. No pump consistently increased the milk volume obtained significantly.In relation to nutrient quality, hand expression or a large electric pump were found to provide higher protein than a manual pump, and hand expression provided higher sodium and lower potassium compared to a large electric pump or a manual pump. Fat content was higher with breast massage when pumping; no evidence of difference was found for energy content between methods.No consistent effect was found related to prolactin change or effect on oxytocin release with pump type or method. Economic aspects were not reported.

AUTHORS' CONCLUSIONS

The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low-cost interventions including initiation of milk expression sooner after birth when not feeding at the breast, relaxation, massage, warming the breasts, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Variation in nutrient content across methods may be relevant to some infants. Small sample sizes, large standard deviations, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings. Independently funded research is needed for more trials on hand expression, relaxation and other techniques that do not have a commercial potential.

How UK internet websites portray breast milk expression and breast pumps: a qualitative study of content

Background

Exclusive breastfeeding for six months is recommended but few parents achieve this; particularly younger and less well-educated mothers. Many parents introduce infant formula milk to manage feeding but describe a desire to express breastmilk alongside a lack of support or information. The Internet is highlighted as a key resource. This study aimed to examine UK websites on expressing breastmilk to identify key messages and how information is provided.

Methods

We used search terms in Google to identify websites with information rich content on expressing breastmilk and breast pumps. Ten sites were purposively selected at two time points in 2013 and 2014 to represent 3 categories: commercial, NHS or 3^rd sector (voluntary or not for profit). Each site was reviewed by two researchers, data and reflective analytical notes were uploaded into NVivo and thematic data analysis undertaken.

Results

Sites varied considerably in their design, use of images, videos, audio files, product placement and marketing opportunities. Three key themes emerged: depiction of expressing; reasons to express; and recommendations about expressing. Inconsistent and conflicting information was common within and between sites. Expressing was portrayed as similar to, but easier than, breastfeeding although at the same time difficult and requiring to be learned. Expressed breastmilk is promoted by mainly commercial sites as immediately available, although pumps were also presented as needing to be concealed, not heard or seen. Health benefits were the overarching reason for expressing. Although predicated on separation from the baby, commercial sites identified this as a positive choice while other sites focused on separation due to circumstance. Commercial sites emphasised restrictions related to breastfeeding, lack of sleep and bonding with the father and wider family. Non-commercial sites emphasised hand expression, with some not mentioning breast pumps. Practical information about starting expressing in relation to infant age or duration of breastfeeding was conflicting.

Conclusions

Internet information about expressing breastmilk is inconsistent, incomplete and not evidence informed. The lack of research evidence on the relationship between expressing and feeding outcomes has provided opportunities for commercial companies, which have the potential to further exacerbate observed health inequalities. Access to good quality information based on robust evidence is urgently required.

Methods of milk expression for lactating women

BACKGROUND

This is an update of a 2008 Cochrane review. Breastfeeding is important. However, not all infants can feed at the breast and methods of expressing milk need evaluation.

OBJECTIVES

To assess acceptability, effectiveness, safety, effect on milk composition, contamination and cost implications of methods of milk expression.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2014), CINAHL (1982 to March 2014), conference proceedings, secondary references and contacted researchers.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing methods at any time after birth.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed trials, extracted data and assessed risk of bias.

MAIN RESULTS

This updated review includes 34 studies involving 1998 participants, with 17 trials involving 961 participants providing data for analysis. Eight studies compared one or more types of pump versus hand expression and 14 studies compared one type of pump versus another type of pump, with three of these studies comparing both hand expression and multiple pump types. Fifteen studies compared a specific protocol or adjunct behaviour including sequential versus simultaneous pumping protocols (five studies), pumping > 4 times per day versus < 3 times per day (one study), provision of a milk expression education and support intervention to mothers of preterm infants versus no provision (one study), provision of audio/visual relaxation to mothers of preterm infants versus no specific relaxation (two studies), commencing pumping within one hour of delivery versus between one to six hours (one study), breast massage before or during pumping versus no massage (two studies, of which one also tested a second behaviour), therapeutic touch versus none (one study), warming breasts before pumping versus not warming breasts (one study), combining hand expression with pumping versus pumping alone (one study) and a breast cleansing protocol versus no protocol (one study).There were insufficient comparable data on outcomes to undertake meta-analysis and data reported relates to evidence from single studies.Only one of the 17 studies examining maternal satisfaction/acceptability provided data in a way that could be analysed, reporting that mothers assigned to the pumping group had more agreement with the statement 'I don't want anyone to see me pumping' than mothers in the hand expression group and the statement 'I don't want anyone to see me hand expressing' (n = 68, mean difference (MD) -0.70, 95% confidence interval (CI) -1.25 to -0.15, P = 0.01), and that mothers found instructions for hand expression were clearer than for pumping (n = 68, MD 0.40, 95% CI 0.05 to 0.75, P = 0.02). No evidence of a difference was found between methods related to adverse effects of milk contamination (one study, n = 28, risk ratio (RR) 0.89, 95% CI 0.62 to 1.27, P = 0.51), (one study, n = 142 milk samples, MD 0.20, 95% CI -0.18 to 0.58, P = 0.30), (one study, n = 123 milk samples, MD 0.10, 95% CI -0.29 to 0.49, P = 0.61), (one study, n = 141 milk samples, MD -0.10, 95% CI -0.46 to 0.26, P = 0.59 ); or level of maternal breast or nipple pain or damage (one study, n = 68, MD 0.02, 95% CI -0.67 to 0.71, P = 0.96).For the secondary outcomes, greater volume was obtained when mothers with infants in a neonatal unit were provided with a relaxation tape or music-listening interventions to use while pumping, when the breasts was warmed before pumping or massaged while pumping.Initiation of milk pumping within 60 minutes of birth of a very low birthweight infant obtained higher mean milk quantity in the first week than the group who initiated pumping later. No evidence of difference in volume was found with simultaneous or sequential pumping or between pumps studied. Differences between methods was found for sodium, potassium, protein and fat constituents; no evidence of difference was found for energy content.No consistent effect was found related to prolactin change or effect on oxytocin release with pump type or method. Economic aspects were not reported.Most studies were classified as unclear or low risk of bias. Most studies did not provide any information regarding blinding of outcome assessment. Fifteen of the 25 studies that evaluated pumps or products had support from the manufacturers.

AUTHORS' CONCLUSIONS

The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low-cost interventions including early initiation when not feeding at the breast, listening to relaxation music, massage and warming of the breasts, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Small sample sizes, large standard deviations, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings.

Randomized trial comparing the effectiveness of 2 electric breast pumps in the NICU

BACKGROUND

Mothers with preterm infants may need to express milk for considerable periods. Research to improve breast pump design has focused on compression stimuli, frequencies, and vacuums.

OBJECTIVE

This study aimed to compare the effectiveness of 2 electric pumps: Medela Symphony (pump S) and a novel pump (Philips AVENT Twin electronic pump; pump A). Both offer flexibility of rate and suction; pump A also incorporates petal compression cushions. Primary outcomes were (1) milk weight expressed during 10-day study period and (2) weight of milk expressed in a 15-minute test.

METHODS

Seventy-one mothers with preterm infants < 34 weeks were randomized. Mothers completed 10-day diaries including weight of milk expressed. Milk weight expressed during a single 15-minute test period and data on pumping mode, skin-to-skin contact, breastfeeding at infant discharge, and mothers' opinions of the pump were recorded.

RESULTS

There was no significant difference in milk expressed during the first 10 days between groups. Pump S mothers expressed significantly more milk during a fixed 15-minute period. Mothers using pump A awarded higher scores for certain characteristics of the pump, notably location of control button and ease of use. Similar proportions of infants received breast milk at discharge, but pump A mothers were more likely to be directly breastfeeding (odds ratio, 4.27 [95% confidence interval, 1.29, 14.1]).

CONCLUSION

The breast pumps showed similar effectiveness in terms of milk expression and maternal opinions. The finding that breast pump design may influence breastfeeding at infant discharge merits further investigation.

Effectiveness of four manual breast pumps for mothers after preterm delivery in a developing country

BACKGROUND

Hospital-grade electric pumps may be useful to initiate and sustain adequate milk production for mothers who are unable to breast-feed their babies hospitalized at special care nurseries (SCN), but their cost is generally not affordable for SCN and for most mothers in developing countries. Therefore, manual breast pumps (MBPs) can be an alternative, but the best option is unknown considering clinical parameters and mothers' preference from among currently available MBPs.

OBJECTIVE

To compare the effectiveness of four MBPs in terms of milk volume, nutritional composition, and breast emptying in order to assist in making a choice for health care personnel and mothers in SCN settings. Duration of expression and maternal preference were also evaluated as secondary outcomes.

METHODS

Mothers of preterm infants used 4 MBPs in a random order, 2 with a squeeze-handle mechanism (Isis and Harmony) and 2 with a cylindrical mechanism (Little Heart and Evenflo), both at the hospital and in home settings using each pump over one 24-hour period.

RESULTS

Milk volume, nutritional composition, breast emptying, and duration of expression were not different among MBPs. Scale of maternal preference rated higher those with the squeeze-handle mechanism than the cylindrical mechanism (p < 0.05).

CONCLUSIONS

There was no difference found in the effectiveness across the four pumps tested. The mothers' rating for comfort and ease of use showed a marked difference between pumps. These factors, plus cost, need to be considered when evaluating manual pumps for use in SCN settings in developing countries.

Effects of Self-breast Pumping in Primiparous Women after Cesarean Delivery

PURPOSE

This study was done to identify the effects of self-breast pumping on breastfeeding rates and, the degree of breast milk fullness among primiparous women giving birth by cesarean section.

METHODS

The study design was a non-synchronized posttest control group experiment with repeated measures. The participants were 60 women, 31 in the experimental group who used a manual pump 5 times a day after exclusive breastfeeding and 29 in the control group who breastfed exclusively with no other interventions.

RESULTS

While self-breast pumping did not improve breastfeeding rates or the degree of breast milk fullness at any of the time points studied, breastfeeding rates continued to remain high till 12 weeks postpartum in both groups.

CONCLUSION

Although some modifications in research methods will be required to identify the effects of breast pumping and exclusive breastfeeding, both these approaches can be used as interventions to improve breastfeeding rates and breast milk quantity.

Development of the breast milk expression experience measure

Exclusive breastfeeding provides optimal nutrition through 6 months. Recent research has shown that milk expression may affect breastfeeding duration. A woman's experience with milk expression might mediate the effect of milk expression on breastfeeding duration. The objective of this study was to develop a measure to evaluate women's experiences of expressing milk. Based on the available literature, we developed a brief measure of the Breast Milk Expression Experience (BMEE) assessing three dimensions: (1) social support for milk expression; (2) ease of learning how to express milk; and (3) personal experiences of milk expression. All items used 1-5 Likert scales, with higher scores indicating better experiences. We administered the items immediately after expression to 68 mothers who expressed milk post-partum. We evaluated this measure for reliability using Cronbach's alpha. Mothers completing the BMEE were 57% primiparous with 75% vaginal births. The BMEE demonstrated appropriate reliability with a Cronbach's alpha of 0.703 for the summary index and 0.719-0.763 for social support, learning experience and personal experience subscales. The BMEE also indicated good predictive validity; of the six mothers who had a mean score <3 on the 11-item scale post-partum, two (33.3%) were expressing breast milk at 1 month, compared with 37 (80.4%) of the 46 mothers who had a mean score ≥3 on the 11-item scale post-partum (P = 0.012). The BMEE is a promising measure of milk expression experience in this population. Use of this measure may allow improved understanding of women's experiences expressing milk.

Methods of milk expression for lactating women

BACKGROUND

This is an update of a 2008 Cochrane review. Breastfeeding is important. However, not all infants can feed at the breast and methods of expressing milk need evaluation.

OBJECTIVES

To assess acceptability, effectiveness, safety, effect on composition, contamination and cost implications of methods of milk expression.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (20 January 2011), CINAHL (1982 to January 2011), conference proceedings, secondary references and contacted researchers.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing methods at any time after birth, and crossover trials commencing at least 28 days after birth.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed trials, extracted data and assessed risk of bias. Data were checked for accuracy.

MAIN RESULTS

We included 23 studies with 10 studies (632 mothers) providing data for analysis.Mothers provided with a relaxation tape produced more milk than mothers who were not (mean difference (MD) 34.70 ml/single expression, 95% confidence interval (CI) 9.51 to 59.89, P = 0.007). A lower milk volume over six days was reported when comparing hand expression to the electric pump (standardised mean difference (SMD) -1.00 ml, 95% CI -1.64 to -0.36, P = 0.002); other studies of the same pump using different measures did not find a significant difference (12 to 36 hours postpartum SMD -0.38 cc, 95% CI -0.86 to 0.10, P = 0.12); day five postpartum SMD -0.62 ml/day, 95% CI -1.43 to 0.19, P = 0.13). No evidence of difference in volume was found with simultaneous or sequential pumping, or between manual and electric pumps studied. One study reported a higher sodium concentration in hand expressed milk compared to a manual pump (SMD 0.59 mmol/L, 95% CI 0.22 to 0.96, P = 0.002) and to an electric pump (SMD 0.70 mmol/L, 95% CI 0.32 to 1.09, P = 0.0003), and lower potassium concentration compared to a manual pump (MD -0.37 mmol/L, 95% CI 0.00 to 0.73, P = 0.05) or to an electric pump (SMD -0.32 mmol/L, 95% CI -0.69 to 0.06, P = 0.10). No evidence of difference was found for energy content, milk contamination or adverse effects. Reports of maternal views were not comparable. Economic aspects were not reported.  

AUTHORS' CONCLUSIONS

The most suitable method for milk expression may depend on the time since birth, purpose of expression and the individual mother and infant. Low cost interventions including early initiation when not feeding at the breast, relaxation, hand expression and lower cost pumps may be as effective, or more effective, than large electric pumps for some outcomes. Small sample sizes, large standard deviations, small number of studies reviewed, and the diversity of the interventions argue caution in applying these results beyond the specific method tested in the specific settings.

Breastfeeding women's experience of expressing: a descriptive study

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.

Serum lutein concentrations in healthy term infants fed human milk or infant formula with lutein

Background

Lutein is a carotenoid that may play a role in eye health. Human milk typically contains higher concentrations of lutein than infant formula. Preliminary data suggest there are differences in serum lutein concentrations between breastfed and formula-fed infants.

Aim of the study

To measure the serum lutein concentrations among infants fed human milk or formulas with and without added lutein.

Methods

A prospective, double-masked trial was conducted in healthy term formula-fed infants (n = 26) randomized between 9 and 16 days of age to study formulas containing 20 (unfortified), 45, 120, and 225 mcg/l of lutein. A breastfed reference group was studied (n = 14) and milk samples were collected from their mothers. Primary outcome was serum lutein concentration at week 12.

Results

Geometric mean lutein concentration of human milk was 21.1 mcg/l (95% CI 14.9–30.0). At week 12, the human milk group had a sixfold higher geometric mean serum lutein (69.3 mcg/l; 95% CI 40.3–119) than the unfortified formula group (11.3 mcg/l; 95% CI 8.1–15.8). Mean serum lutein increased from baseline in each formula group except the unfortified group. Linear regression equation indicated breastfed infants had a greater increase in serum lutein (slope 3.7; P < 0.001) per unit increase in milk lutein than formula-fed infants (slope 0.9; P < 0.001).

Conclusions

Breastfed infants have higher mean serum lutein concentrations than infants who consume formula unfortified with lutein. These data suggest approximately 4 times more lutein is needed in infant formula than in human milk to achieve similar serum lutein concentrations among breastfed and formula fed infants.

Maternal response to two electric breast pumps

BACKGROUND AND OBJECTIVE

Mechanical characteristics of breast pumps have been shown to influence milk extraction and hormone release in laboratory settings. However, few studies evaluate impact of differences in pump design on long-term breastfeeding success. This study evaluated the impact of a novel pump design on milk extraction, milk fat content, maternal hormone response, maternal satisfaction, long-term milk production, and duration of breastfeeding following return to the workforce.

DESIGN AND METHODS

Healthy women intending to return to work or school and to breastfeed exclusively for <or=4 months were enrolled in late pregnancy (n = 62). Prolactin response to pumping (n = 30) and changes in 24-hour milk volume during a 2-week stimulation protocol (n = 59) were measured in women randomly assigned to a novel (Embrace, Playtex, Westport, CT) or standard (Pump In Style, Medela, Baar, Switzerland) electric breast pump. Milk extraction efficiency (n = 58) and maternal ranking of pump performance (n = 56) were measured using a crossover design. Mothers selected one pump to keep and were contacted (n = 55) at 6 months postpartum to determine breastfeeding behavior.

RESULTS

Prolactin response was greater (p = 0.005) with the novel pump. Milk extraction efficiency was greater (p = 0.001) with the standard pump. Stimulation of 24-hour milk production did not differ between pumps. Women were equally likely to select the two pumps. Feeding behavior at 6 months was not related to pump choice.

CONCLUSIONS

The test pumps stimulate the two arms of the homeostatic mechanism governing milk output (endocrine stimulation and degree of breast emptying) to different degrees, yet have comparable impacts on lactation performance over time.

Methods of milk expression for lactating women

BACKGROUND

Breastfeeding is important for health. However, not all infants can feed at the breast and effective methods of expressing milk have not been adequately evaluated.

OBJECTIVES

To assess acceptability, effectiveness, safety, effect on milk composition, bacterial contamination of milk and cost implications of a range of methods of milk expression, including hand expression and manual, battery and electric pumps.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (December 2007), CINAHL (1982 to July 2007), handsearched relevant journals and conference proceedings, scanned secondary references and contacted experts in the field.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials that compared one method or technique of milk expression or pumping with other(s), at any time after birth, and cross-over trials that commenced at least 28 days after birth.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We sought additional information from the trial authors.

MAIN RESULTS

Twelve studies met the inclusion criteria of which six (397 mothers) provided data that could be used in the analyses. Compared with hand expression, one study found a significantly greater total volume of milk expressed over six days both with the electrical pump (373.10 ml, 95% confidence interval (CI) 161.09 to 585.11), and with the foot-operated pump (212.10 ml, 95% CI 9.39 to 414.81); however, the difference found between the foot pump and the electric pump was not significant. Mothers provided with a relaxation tape produced a greater volume of milk at one expression than women not provided with the tape (34.70 ml, 95% CI 9.51 to 59.89). Simultaneous pumping took less time than sequential pumping in one study (3.50 hours/week, 95% CI 1.39 to 5.61). No evidence of difference was found in volume with simultaneous or sequential pumping, or for milk contamination, breastfeeding at discharge, fat content of milk, serum prolactin by method of pumping. Maternal satisfaction, adverse effects on mothers and economic effects of interventions were poorly reported.

AUTHORS' CONCLUSIONS

Mothers appear to obtain greater total volumes of milk in six days after birth using the electric or foot powered pump tested compared to hand expression, and a greater volume at one expression during the second week when provided with a relaxation tape. Simultaneous pumping takes less time compared to sequential pumping. Further research with larger numbers and more comprehensive reporting is needed, and mothers' reasons for expressing linked to their evaluation of effectiveness rather than market-led research on equipment performance.

Comparison of manual and electric breast pumps among WIC women returning to work or school in Hawaii

INTRODUCTION

The Women, Infants, and Children (WIC) branch of the Hawaii Department of Health encourages and assists mothers in breastfeeding. A study was done to determine whether an electric breast pump (vs. a manual pump) would increase breastfeeding duration in those returning to work or school full-time.

MATERIALS AND METHODS

During 2002-2003, a randomized trial was conducted among 280 women, with the duration of breastfeeding analyzed in 229 of these women. Descriptive analyses and a multivariate logistic regression analysis assessed factors associated with breastfeeding at 6 months. Unadjusted and adjusted survival analyses were performed to estimate the duration of breastfeeding.

RESULTS

In all, 76.8% of women using the manual breast pump and 72.3% of those using the electric breast pump breastfed for at least 6 months. This difference did not reach statistical significance. In the survival analysis adjusted for pump assignment, maternal age, race/ethnicity, marital status, and parity, women with at least some college education breastfed for a 38% shorter time than women with a high school or lower education.

CONCLUSIONS

Our findings suggest that the manual breast pump may work as well as the electric breast pump when breastfeeding is encouraged and supported among women returning to work or school full-time. Particular attention should be given to examining reasons why women with greater education breastfed for a shorter duration. Further research is needed to validate these results to better inform breastfeeding women returning to work or school.