Speculating about the ramifications their findings had on efforts to encourage women to breastfeed, the authors concluded promotional material may need to be adapted accordingly, to reflect "socio-cultural background".
They said: "Our results suggest that women living in a country or region where Catholicism has historically dominated are less likely to initiate breastfeeding, and that breastfeeding promotion policies should be adapted to better fit populations' cultural and religious norms."
Data on breastfeeding rates and figures regarding Catholic and Protestant populations from 135 countries were included in the research, which also examined regional statistics from the UK, Ireland, France, the USA and Canada.
Calling for more research to examine their finding, the authors added: "Studies are also necessary to identify the sociocultural values and beliefs that mediate the relationships between a historically Catholic family or societal background and breast feeding."