A new study in the Canadian Medical Association Journal, Michael Kramer – an internationally recognized researcher in this area – and colleagues examined over 3 million births recorded in Canada between 1985 and 1998 to determine if weekend delivery in a country with universal health insurance was riskier on weekends. They found infants born during the weekend had "slightly but significantly elevated risks of stillbirth and neonatal death" (about 6% greater) than infants born on weekdays. The difference was reduced when the authors took into account the length of gestation, a known risk factor for stillbirth and neonatal death.
The authors state that the disappearance of excess risk of overall stillbirth and early neonatal death after adjustment for gestational age can probably be explained by the selective timing of low-risk elective deliveries, most of which are timed to occur on weekdays.
p. 337 Risks of stillbirth and early neonatal death by day of the week -- Z.-C. Luo et al
Canadian Medical Association Journal