Article Text

Download PDFPDF
Predictors of expressed breast milk volume in mothers expressing milk for their preterm infant
  1. M S Fewtrell1,
  2. K Kennedy1,
  3. J S Ahluwalia2,
  4. R Nicholl3,
  5. A Lucas1,
  6. P Burton1
  1. 1Childhood Nutrition Research Centre, UCL Institute of Child Health, London, UK
  2. 2Neonatal Intensive Care Unit, Addenbrookes Hospital, Cambridge, UK
  3. 3Neonatal Intensive Care Unit (NICU), Northwick Park Hospital, Harrow, Middlesex, UK
  1. Correspondence to Dr M S Fewtrell, Childhood Nutrition Research Centre, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK; m.fewtrell{at}


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.

  • Infant Feeding
  • Neonatology

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Contributors Study concept and design: MSF, AL. Study conduct and data collection: PB, KK, RN, JSA. Data analysis: MSF, PB. Writing the initial draft of the manuscript: MF. Critical appraisal and finalising the manuscript: all authors.

  • Funding This study was supported by a grant from Philips AVENT (Philips Consumer Lifestyle, Amsterdam, the Netherlands), who also provided the breast pumps, and sponsored by the UCL Institute of Child Health.

  • Competing interests MSF, KK and PB have received research funding from and conducted advisory work for Philips AVENT.

  • Ethics approval National Research Ethics Service Committee London—Bloomsbury 08/H0713/85.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement The majority of data collected in the trial have now been published or submitted for publication. Data are available from MSF subject to discussion about planned use.

Linked Articles

  • Fantoms
    Ben Stenson