In studies conducted several decades ago, births on weekends were fewer
than expected, and neonatal mortality was higher, consistent with current
concerns about the quality of weekend medical care. In this analysis of 1995-1997
California linked data from birth and infant death certificates, Gould and
colleagues found that observed neonatal mortality increased from 2.80 per
1000 births on weekdays to 3.12 per 1000 on weekends, but after adjusting
for birth weight, the increase in neonatal mortality for infants born on weekends
was not statistically significant.