Overweight and obesity affect more than 50% of women of reproductive age in the US and are associated with many adverse outcomes during and after pregnancy, for both mother and offspring. In this issue of JAMA Pediatrics, Tanner et al reported the risk of sudden unexpected infant death (SUID) according to maternal weight status in a large national database. They found that the infants of mothers with prepregnancy body mass index (BMI) in the obesity categories (ie, BMI ≥30; calculated as weight in kilograms divided by height in meters squared) were at higher risk of SUID in the first year of life, with an apparent dose-response association. Although this is not totally surprising given the many adverse outcomes in pregnancy and in early life for offspring of pregnant individuals living with obesity, this report raises 2 main questions: (1) If prepregnancy obesity is causal, what are the mechanisms? (2) What strategies can we use to reduce the risk of this devastating outcome in this population?