The aim of this study was to analyse different behavioural traits of sows to describe posture changes and to determine the influences of these traits on piglet losses. Twenty sows which crushed one or more than one piglet (C-sows) were compared to 20 sows which crushed no piglets (NC-sows). It is concluded that the results suggest posture patterns of non crushing-sows and Crushing-sows are different, especially nest-building behaviour prepartum and ventral or lateral recumbence postpartum, indicating a possible use to characterise the maternal abilities of sows in minimising piglet crushing.