Abstract
Milk ejection is essential for effective milk removal during breastfeeding and pumping, and for continued milk synthesis. Many women are unable to accurately sense milk ejection to determine whether their infant is receiving milk or, when pumping, to switch the pump to a more effective expression pattern. To determine if changes in bioimpedance parameters are associated with milk ejection in the lactating breast during pumping. 30 lactating women participated in 2 pumping sessions within 2 weeks of each other. During pumping the breasts were monitored with bioimpedance spectroscopy (on either the pumped or the non- pumped breast), and milk flow rate and volume were measured simultaneously. All mothers completed 24-h milk productions. Linear mixed effects models were used to determine associations between milk flow rate and bioimpedance changes. Changes in bioimpedance parameters were greater at the first milk ejection when measured on the pumped breast (median (IQR): R zero: −7 (−17, −4,) % (n = 30); R infinity: −8 (−20, −2) % (n = 29); membrane capacitance: −24 (−59, −7) % (n = 27). Changes in bioimpedance detected in the non-pumped breast were lower at the first milk ejection, R zero: −3 (−8, −2) % (n = 25); R infinity: −5 (−8, −2) % (n = 23); membrane capacitance: −9 (−17, 15) % (n = 24). Smaller less consistent decreases in the bioimpedance characteristics were detected at the second milk ejection in both breasts. Bioimpedance parameters showed a consistent decrease associated with the first milk ejection when electrodes were placed on the pumped breast. Smaller decreases were observed when the non-pumped breast was monitored for the first and second milk ejection. There was wide variation in the magnitude of changes observed, and hence further development of the methodology is needed to ensure reliability.
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The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
References
Truchet S, Honvo-Houéto E. Physiology of milk secretion. Best Pract Res Clin Endocrinol Metab. 2017;31:367–84.
Kent JC, Ramsay DT, Doherty D, Larsson M, Hartmann PE. Response of breasts to different stimulation patterns of an electric breast pump. J Hum Lact. 2003;19(2):179–86.
Ramsay DT, Mitoulas LR, Kent JC, Cregan MD, Doherty DA, Larsson M, et al. Milk flow rates can be used to identify and investigate milk ejection in women expressing breast milk using an electric breast pump. Breastfeed Med. 2006;1(1):14–23.
Ramsay DT, Kent JC, Owens RA, Hartmann PE. Ultrasound imaging of milk ejection in the breast of lactating women. Pediatrics. 2004;113(2):361–7.
Luther E, Arballo J, Sala N, Cordero Funes J. Suckling pressure in humans: relationship to oxytocin-reproducing reflex milk ejection. J Appl Physiol. 1974;36(3):350–3.
Prime DK, Geddes DT, Hepworth AR, Trengove NJ, Hartmann PE. Comparison of the patterns of milk ejection during repeated breast expression sessions in women. Breastfeed Med. 2011;6(4):183–90.
Kyle UG, Bosaeus I, De Lorenzo AD, Deurenberg P, Elia M, Gómez JM, et al. Bioelectrical impedance analysis—part I: review of principles and methods. Clin Nutr. 2004;23(5):1226–43.
Cornish B, Chapman M, Hirst C, Mirolo B, Bunce I, Ward L, et al. Early diagnosis of lymphedema using multiple frequency bioimpedance. Lymphology. 2001;34(1):2–11.
Ward LC. Bioelectrical impedance spectrometry for the assessment of lymphoedema: principles and practice. Lymphedema: Springer; 2015. p. 123–32.
Bera TK. Bioelectrical impedance methods for noninvasive health monitoring: a review. J Med Eng. 2014;2014:1–28.
Gowry B, Shahriman A, Paulraj M, editors. Electrical bio-impedance as a promising prognostic alternative in detecting breast cancer: a review. Biomedical Engineering (ICoBE), 2015 2nd International Conference on; 2015: IEEE.
Malecka-Massalska T, Chara K, Golebiowski P, Wladysiuk M, Smolen A, Kurylcio A, et al. Altered tissue electrical properties in women with breast cancer–preliminary observations. Ann Agric Environ Med. 2013;20(3).
Tornuev YV, Koldysheva E, Lapiy G, Molodykh O, Balakhnin S, Bushmanova G, et al. Bioimpedancemetry in the diagnostics of inflammatory process in the mammary gland. Bull Exp Biol Med. 2014;156(3):381–3.
Arthur P, Hartmann P, Smith M. Measurement of the milk intake of breast-fed infants. J Pediatr Gastroenterol Nutr. 1987;6(5):758–63.
Fleet I, Linzell J. Rapid method of estimating fat in very small quantities of milk. J Physiol Lond. 1964;175(1):P15–7.
Prime DK, Geddes DT, Spatz DL, Robert M, Trengove NJ, Hartmann PE. Using milk flow rate to investigate milk ejection in the left and right breasts during simultaneous breast expression in women. Int Breastfeed J. 2009;4(1):10.
Gardner H, Kent JC, Lai CT, Mitoulas LR, Cregan MD, Hartmann PE, et al. Milk ejection patterns: an intra-individual comparison of breastfeeding and pumping. BMC Pregnancy Childbirth. 2015;15(1):156.
Studio Team R, Studio R. Integrated development for R. Boston, MA: R Studio Inc.; 2015.
Pinheiro J, Bates D, DebRoy S, Sarkar D. Linear and nonlinear mixed effects models. R package version. 2007;3:57.
Lenth RV. Least-squares means: the R package lsmeans. J Stat Softw. 2016;69(1):1–33.
Ward L, Sharpe K, Edgar D, Finlay V, Wood F, editors. Measurement of localized tissue water–clinical application of bioimpedance spectroscopy in wound management. J Phys Conf Ser; 2013: IOP Publishing.
DeNuccio D, Grosvenor C. Effects of volume and distribution of milk on the oxytocin-induced contraction of the lactating rat mammary gland in vivo. J Endocrinol. 1971;51(3):437–46.
Prime DK, Kent JC, Hepworth AR, Trengove NJ, Hartmann PE. Dynamics of milk removal during simultaneous breast expression in women. Breastfeed Med. 2012;7(2):100–6. https://doi.org/10.1089/bfm.2011.0013.
Ramsay D, Kent J, Hartmann R, Hartmann P. Anatomy of the lactating human breast redefined with ultrasound imaging. J Anat. 2005;206(6):525–34.
Geddes DT, Aljazaf KM, Kent JC, Prime DK, Spatz DL, Garbin CP, et al. Blood flow characteristics of the human lactating breast. J Hum Lact. 2012;28(2):145–52.
Eriksson M, Lundeberg T, Uvnäs-Moberg K. Studies on cutaneous blood flow in the mammary gland of lactating rats. Acta Physiol Scand. 1996;158(1):1–6.
Acknowledgements
This research was funded by an unrestricted research grant from Medela, Ag, Baar Switzerland .
The authors would like to thank the participants, and the Australian Breastfeeding Association (WA Branch) for their support (Approval 2016-1).
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HG, CTL & DG are supported by an unrestricted research grant from Medela AG.
The study was approved by The University of Western Australia Human Research Ethics Committee (RA/4/1/7897).
All participants provided written informed consent.
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Author Ward provides consultancy services to ImpediMed Ltd. ImpediMed had no input into the conception or conduct of the study or the writing of the manuscript.
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Gardner, H., Lai, C., Ward, L. et al. Detection of Milk Ejection Using Bioimpedance Spectroscopy in Lactating Women during Milk Expression Using an Electric Breast Pump. J Mammary Gland Biol Neoplasia 24, 177–184 (2019). https://doi.org/10.1007/s10911-019-09426-2
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DOI: https://doi.org/10.1007/s10911-019-09426-2