The objectives of this study was to determine the relationship between individual piglet birth weight and the odds of survival until weaning and differences due to sow parity. Piglets in this study were purebred Yorkshire (n=70763), purebred Landrace (n=51091), purebred Duroc (n=16834), and Landrace x Yorkshire or Yorkshire x Landrace (n=38447) reciprocal F1 piglets. Data were recorded from sows in four production units within the same genetic flow from September 2009 through November 2013. Piglets were individually weighed and identified within 24 hours of birth and cross-fostering was completed within 48 hours of birth. Survival was defined as the piglet’s ability to survive from birth until weaning (mean=22.9 ± 3.3 days). During analysis, piglets were categorized into birth weight classes based on their individual birth weight. Data were analyzed using logistic binomial regression to estimate the odds ratio of survival until weaning among birth classes and parity. Odds to survival were generally higher as birth weight increased and piglets weighing 1.60-2.05 kg showed an increase in odds ratio of pre-weaning survival relative to all other piglets. As parity increased, the odds of surviving decreased. Piglets from parity 1 and 2 sows, showed (P<0.001) higher odds ratios of surviving, in relation to piglets from parity 3-8 sows.