this paper describes the use of breast pumps amongst a group of mothers of healthy term infants in Melbourne, Australia, between birth and six months post partum.a prospective cohort study; data were collected using structured questionnaires.1003 postpartum women who had given birth to healthy infants at term were recruited from three Melbourne maternity hospitals between July 2009 and April 2011. Data were collected by face-to-face interview at recruitment and by telephone interview three and six months later.at recruitment (24 to 48 hours post partum), 60% (605/1003) of women already had a breast pump. At two weeks post partum expressing was common; 62% (290/466) of women had expressed by this time, with 40% (186/466) doing so several times a day. By six months post partum 83% (754/911) of the women had a breast pump and 40% (288/715) were expressing, although most just occasionally. The most common reasons for any expressing in the first six months were 'to be able to go out and leave the baby' (35%; 268/772); milk supply 'not enough'(27%; 207/772); and having 'too much' milk (19%; 147/772). The increasing popularity of expressing breast milk to feed infants is not driven by women returning to the workforce, as only 10% of women (80/772) expressed because they had returned to paid employment.health professionals should be aware that in some settings breast pump use is common in the first six months, and this is not always related to maternal workforce participation.