Background
Low birthweight (LBW) children have a higher risk of neonatal mortality. All institutional deliveries, therefore, should be weighed to determine appropriate care. Mortality risk for newborns who are not weighed at birth (NWB) is unknown.

Methods
This paper used logit regression models to compare the odds of death for NWB neonates to that of other neonates using data on 401 712 institutional births collected in Demographic and Health Surveys from 32 low- and middle-income countries.

Results
In the pooled sample, 2.3% died in the neonatal period and 12% were NWB. NWB neonates had a high risk of mortality compared to normal birthweight children (Adjusted odds ratio [AOR] 5.8, 95% CI: 5.3, 6.5). The mortality risk associated with NWB was higher than for LBW. The neonatal mortality risk associated with NWB varied across countries from AOR of 2.1 (95% CI: 1.22, 3.8) in Afghanistan to 94 (95% CI: 22, 215) in Gabon. In the pooled sample, the 12% of children who were NWB accounted for 37% of all neonatal deaths.

Conclusions
The association between NWB and neonatal mortality may suggest a need to focus on the quality of institutions related to newborn care. However, further studies are needed to determine causality. A health emergency or death may also cause NWB