Background Historically, breastfeeding rates in Ireland have been low compared with international averages. It has been suggested that maternal ethnicity and citizenship may influence breastfeeding rates, with ethnic minorities thought more likely to breast feed.

Aim The aim of this study is to investigate the association among maternal citizenship, ethnicity, birthplace and breast feeding. It is hypothesised that Irish mothers (identified through Irish citizenship, self-identified Irish ethnicity or Irish birthplace) are less likely to breast feed than non-Irish mothers.

Methods The study population of Growing Up in Ireland: the National Longitudinal Study of Children was used for this study. Analysis was restricted to 11 092 biological mother and infant pairs with a complete breastfeeding history. Logistic regression analysis was used to estimate ORs and 95% CIs for breast feeding relative to maternal citizenship and ethnicity, controlling for the confounding effects of other maternal variables.

Results Results indicated that 55.9% (6202 of 11 092) of mothers had initiated breast feeding, with only 7.9% (874 of 11 092) of mothers currently breast feeding their infant (at 9 months of age). Irish citizens (4693 of 9368, 50.0%) were significantly less likely to have initiated breast feeding compared with non-Irish citizens (1503 of 1695, 88.7%). Irish born mothers (4179 of 8627, 48.8%) were also significantly less likely to have initiated breast feeding than mothers born elsewhere (2023 of 2462, 82.2%).

Conclusions Maternal citizenship and ethnicity appear to be the strongest influencing factors on breastfeeding initiation and duration. However, this raises a possibility that the increase in breastfeeding rates seen recently may be the result of increased immigration into Ireland, rather than the success of policy and research efforts.