Babies in the United States are significantly more likely to be born on Tuesdays than on Sundays.

Data from the National Center for Health Statistics (NCHS) consistently shows that Tuesday is the most popular day for births in the United States. According to a 2013 report by the Centers for Disease Control and Prevention (CDC), an average of 12,501 births occurred each Tuesday, compared to just 7,363 on Sundays. This represents a staggering 41% difference between the most and least active days of the week.The primary reason for this disparity is the rise of scheduled deliveries. In the 1950s, births were distributed more evenly across the week because they mostly happened naturally. Today, nearly one in three U.S. births is via Cesarean section, and many others are induced. Doctors and hospitals prefer to schedule these elective procedures between Monday and Friday to ensure that specialized surgical teams and neonatal staff are fully available.Tuesday often sees the highest volume because it avoids the logistical backlog that can occur on Mondays after a weekend. Conversely, weekend birth rates have plummeted because medical staff generally only perform emergency procedures on Saturdays and Sundays. This shift has effectively moved the 'natural' timing of birth into a managed medical schedule.Researchers have noted that this trend is even more pronounced on federal holidays. For example, birth rates on Thanksgiving or Christmas are often as low as or lower than Sunday rates. This data highlights how modern obstetric practices have fundamentally altered the biological timing of human birth to align with the standard workweek.