Breast milk expression practices, breastfeeding self-efficacy and breastfeeding duration in Hong Kong mothers

Professor Lok, Yuet Wan   (Principal Investigator (PI))

Professor Tarrant Marie   (Co-Investigator)

Professor Fong Daniel Yee Tak   (Co-Investigator)

30

2017-04-30

2019-10-29

150000

Breast milk expression practices, breastfeeding self-efficacy and breastfeeding duration in Hong Kong mothers

Breast milk expression, Breastfeeding

Population HealthNutrition

201702159003

Seed Fund for Basic Research for New Staff

2016

Completed

Breastfeeding provides optimal nutritional benefits for infants’ growth and development. The World Health Organization recommends 6 months of exclusive breastfeeding with continued breastfeeding for up to two years and beyond.[1] To date the majority of breastfeeding studies have focused on factors associated with the initiation, duration, or exclusivity of breastfeeding.[2, 3] In these studies, the term ""breastfeeding"" has normally been used to describe the feeding of human milk to infants by any and all means and studies have rarely distinguished between different modes of human milk delivery (direct feeding at the breast, expressed human milk feeding, or a combination). Researchers in developed countries have documented a growing trend in expressed breast milk feeding among mothers of healthy term babies.[5] Findings in the United States showed that 85% of mothers had expressed breast milk at some point, 68% expressed within the first 2 weeks after birth, and 25% did so on a regular basis.[6] In Australia, one study found that 98% of mothers had expressed human milk at least once.[7] In Hong Kong, data from two breastfeeding cohorts (2006-07 and 2011-2012)[8], showed that the proportion of breastfeeding mothers feeding expressed breast milk at 1 month increased from 28.6% in the first cohort to 41.9% in the second cohort.[9] Furthermore, the proportion of mothers who were only feeding breast milk that was expressed increased from 6.8% in 2006-07 to 18.8% in 2011-12. Studies have also examined the effect of expressed breast milk feeding on the total duration of any breast milk feeding, with conflicting findings. Some studies report no significant associations between expressed breast milk feeding and the total duration of breast milk feeding[10], others have shown both negative[11, 12] and positive relationships[13, 14]. Schwartz et al [15] found that expressed breast milk feeding within the first 3 weeks postpartum was associated with early breastfeeding cessation, whereas expressed breast milk feeding between 4 and 12 weeks postpartum predicted a lower risk of stopping breastfeeding. Similarly, a Hong Kong study found that exclusive expressed breast milk feeding was associated with a shorter duration of breastfeeding across the first 6 months. Overseas studies have reported on reasons why mothers of healthy term infants express breast milk. Commonly reported reasons were experiencing early breastfeeding difficulties, wanting or needing others to feed the baby, the desire to measure milk intake, building an extra supply of milk, to avoid breastfeeding in public, and returning to employment.[7, 16] The increase in breastmilk expression has also been associated with a lack of maternal self-confidence in their ability to breastfeed successfully,[6] especially among new mothers in whom the ability to express and store milk may provide reassurance of their ability to nurture their infants. However, it has been argued that mechanical breast expression could potentially create a dependency on the pump and thus diminish women’s confidence in their ability to nurture their infant.[17] In addition, the reliance on breast pumps further medicalizes the act of breastfeeding, where the focus is more on the product than the process.[18] This reliance on the breast pump, rather than the breast, could end up further eroding maternal breastfeeding confidence and undermining direct breastfeeding.[7] Breastfeeding confidence is best measured using breastfeeding self-efficacy scales. Maternal breastfeeding self-efficacy is defined as a mother’s perceived confidence in her ability to breastfeed her child,[19] which influences her breastfeeding decisions and is significantly associated with a longer duration of breastfeeding.[20] Dennis developed the original breastfeeding self-efficacy scale (BSES) [20] and the subsequent short form of the breastfeeding self-efficacy scale (BSES-SF).[21] The BSES measures three dimensions of successful breastfeeding-technique, intrapersonal thoughts, and support: technique, intrapersonal thoughts, and support. Technique is the physical aspect of breastfeeding; intrapersonal thoughts are a mother’s perceptions of a successful breastfeeding experience, including her attitudes and beliefs; and support is defined as the informational, appraisal, emotional, and instrumental assistance that is available to help a mother succeed at breastfeeding. The BSES-SF has been validated in a wide range of populations [20, 22-24] and when measured in the immediate postpartum period, is highly predictive of continued breastfeeding.[20, 25] Higher BSES-SF scores indicate higher levels of breastfeeding self-efficacy and confidence. The BSES-SF has been translated into Traditional Chinese for use in Hong Kong and has been validated.[23] Breast milk expression is becoming increasingly common. Researchers have raised concerns about the increasing trend of expressed breast milk feeding, [26, 33] especially exclusive expressed breast milk feeding. At present, it is unclear why mothers are choosing to pump rather than directly breastfeed,[11] as research has not adequately explored this aspect of breastfeeding. The increase in expressed breast milk feeding may be because more mothers are choosing expressed breast milk over infant formula. In that context, this is a positive trend as expressed breast milk can provide infants with the superior nutritional benefits when compared with infant formula. Conversely, the increase in breast milk expression may be because new mothers are unaware that the mode of breast milk feeding may be equally as important as the content of the feed, and that expressed breast milk feeding may produce fewer health benefits than direct breastfeeding.[30, 34] Existing studies on breast milk expression practices have a number of substantial limitations. First, few studies have collected separate data on the feeding of the baby and the breast milk expression practices of the mother. Breastfeeding has almost exclusively been examined as a synchronous process whereas breast milk expression has now created a possible distinction between the act of pumping and the act of feeding breast milk.[26] Second, few studies have been designed to specifically collect data on breast milk expression practices and the impact on breastfeeding related outcomes. Third, maternal breastfeeding confidence and self-efficacy are key determinants of continued breastfeeding.[20] Although researchers have speculated that breast milk expression may either enhance or diminish maternal breastfeeding confidence, these hypotheses have never been examined. Finally, there has been few research conducted on breast milk expression in mothers of term infants, as most studies have focused on sick or preterm infants.[5] Few studies have examined why women start expressing breast milk and why they continue to express breast milk. The primary objective of this study is to examine the effect of breast milk expression on maternal breastfeeding self-efficacy. The secondary objectives are to examine the effect of breast milk expression on breastfeeding duration and to examine the attitudes and beliefs toward direct breastfeeding and expressed breastmilk feeding.