Author, year, country | Design | Location, participants, year of study and recruitment | Study aims and outcome measures | Results | Strengths/Limitations |
---|---|---|---|---|---|
Geraghty et al. 2005 USA [1] | Retrospective cohort | Cincinnati, Ohio n = 346 2002 Random selection postal recruitment when infants were between 2 and 3Â years old | Quantify breast pump use | 77% (182/236) ever used a breast pump | Large sample size |
 | Identify relationships between breast pump use and | No significant difference in expressing between 4 groups of mothers; those of | Clear differentiation between breastfeeding and breast milk feeding | ||
 | - singleton vs. multiple pregnancy | - term singletons | Periodic reports re. proportion of expressing versus breastfeeding (at 1 day, 3 days, 2 weeks and monthly until 6 months) | ||
 | - gestation at birth | - preterm singletons | Retrospective data, possible recall bias, initial contact made when children between 2–3 years of age-requesting detailed information about infant feeding at 24 hrs, 3 days, 2 weeks and then at monthly intervals to 6 months. | ||
 | - breastfeeding outcomes | - term multiples | Expressing methods not distinguished between hand, manual or electric pump | ||
- preterm multiples | |||||
- 68% (236/346) received at least some breast milk. | |||||
- 5% (12/236) exclusively expressed to feed – all mothers of premature babies | |||||
Binns et al. 2006 Australia [2] | Longitudinal | Perth, Western Australia | - Explore determinants of breastfeeding | - PIFS I 38% (211/556) expressing by 6 weeks | Large sample |
PIFS I n = 556 | - Measure and compare prevalence of expressing | - PIFS II 69% (405/587) expressing by 4 weeks | Comparison of similar groups 10Â years apart | ||
1992–93 |  | - Expressing rates steadily decline after 6 weeks: | Limited detail about expressed breast milk/ breastfeeding proportions. | ||
PIFS II n = 587 | Â | 26% (145/556) at 24Â weeks in PIFS I 28% (164/587) at 22Â weeks in PIFS II | Public patients only, perhaps not representative | ||
2002–03 |  |  | Differing interview schedules – less clarity for comparison | ||
Recruited in hospital in early postpartum period | Â | Â | Â | ||
Labiner-Wolfe et al. 2008 USA [3] | Longitudinal | National study | - Reasons why women express | - Most common reason: for someone else to feed baby | Large sample |
n = 4606 | - Amount and prevalence of milk expression | - 85% (1329 /1564) between 1.5 and 4.5 months postpartum had expressed at some time since birth | Maternal recall previous 7Â days | ||
2005–2007 | - Associated socio-demographic factors | - 68% (1015/1493) of this group had expressed in 2 weeks before survey, 25% (373/1493) regularly | Measures frequency of expressing (asked how many times expressed in previous 2 weeks and if expressed on a regular schedule) | ||
from IFPS II | Â | - Expressing associated with: maternal employment, higher income, first breastfeeding experience | Not nationally representative: Older, more educated, more likely to be white, employed, higher income, less likely to smoke. More likely to breastfeed and for longer | ||
Mail survey 2, 5 and 7 months postpartum | Â | Â | Â | ||
Shealy et al. 2008 USA [4] | Longitudinal | National study | Describe breastfeeding in first 12 months to identify: | - 0.06% of babies fed expressed breast milk exclusively – 2/3 of these ceased breast milk feeding by 4 weeks | Detailed analysis of feeding type/frequency/duration of individual feeds |
n = 2587 | - Prevalence of exclusive pumping and formula supplementing |  | Limited data re. expressing – except when it was exclusive | ||
2005–2007 | - Patterns and trends in breastfeeding related to common advice given |  |  | ||
from IFPS II | Â | Â | Â | ||
Monthly postal questionnaires | Â | Â | Â | ||
Clemons & Amir 2010 Australia [5] | Cross-sectional | State-wide study, Victoria | - Prevalence of breast milk expression | - 67% (602/898) had fully breastfed prior to hospital discharge | Large study |
n = 903 | - Demographic characteristics of women who express, why and how they do it | - 14% (125/898) had breastfed and expressed to feed their baby | Possible selection bias (members of the Australian Breastfeeding Association) | ||
2008 | - Women’s experience of using breast pumps | - Of those whose youngest child was over six months 95% (628/661) fully breastfed for at least six months | Timing of questionnaire, possible recall bias | ||
Online questionnaire sent to Australian Breastfeeding Association members who had an email address | Â | - 4% (34/898) expressed and exclusively fed EBM | Â | ||
Baby any age | Â | - 98% (885/903) ever expressed | Â | ||
Hornbeak et al. 2010 Singapore [6] | Retrospective cohort | Singapore | - Prevalence and patterns of breastfeeding in Singaporean Chinese mothers from birth to 6 months | - Initiation of breast milk feeding increased from 69% (144/210) in 2000-2001 to 82% (538/656) in 2006/2008 | Large representative sample of Chinese Singaporean mothers |
n = 3009 | Â | - Exclusive expressing increased from 9% (18/144) in 2000-2001 to 18% (118/538) in 2006/2008 | Limited detail about expressed breast milk/breastfeeding proportions. | ||
2006-2008 |  | - Direct breast milk feeding decreased from 34% (72/210) in 2000–2001 to 27% (142/656) in 2006/2008 | Possible recall bias - recruitment 6–72 months after birth | ||
Recruited mothers of 6-72 month Chinese Singaporean children through Strabismus, Amblyopia and Refractive Error in Singaporean Children (STARS) Study | Â | Â | Gestational age not indicated | ||
Mailed invitation | Â | Â | Â | ||
Face-to-face interview | Â | Â | Â | ||
Geraghty et al. 2012 USA [29] | Prospective longitudinal cohort | Cincinnati, Ohio | - Describe who commences expressing early | - 14% (8/59) commenced some expressing in first week | Prospective design assisting recall |
n = 60 | - Explore breastfeeding duration in women who express | - By four weeks: 63% (37/59) expressing | Initial weekly visits; used weekly and 24Â hour recall to enquire about feeding and expressing | ||
2004–2007 |  | - Expressing had no effect on duration of breast milk feeding | Clear differentiation between ‘breastfeeding’ and ‘breast milk feeding’ | ||
Recruited face to face in first week after hospital discharge. | Â | Â | Small study | ||
 |  |  | Recruitment of women who planned to breastfeed for 6 months or more | ||
 |  |  | Mothers recruited for study knew they were going to be assisted to pump and may have been more likely to be comfortable with this. | ||
 |  |  |  |  | Possible introduction of bias as weekly collection of breast milk was initiated at 1 week by research nurse using an electric breast pump |