Maternity ward rush hours? Hospitals report most births from 8 am-1 pm

It’s not exactly accidental that mornings are busy birthing times in U.S. hospitals.

The rise of medical technologies to induce or assist births has also permitted delivery times to coincide with “regular daytime hours,” a federal study finds.

Hospital maternity wards are particularly busy during weekday mornings and early afternoon hours, and far less active once the sun has set, the National Center for Health Statistics (NCHS) said in a report released Friday.

The findings point to the increased use of “medical interventions,” such as induced labor or cesarean delivery, in childbirth, which permit births to be organized around hospital personnel resources and at times the wishes of the parents, NCHS researchers T.J. Mathews and Sally C. Curtin said in the report.

Of course, many babies decide when they will come, but relatively few — around 3 percent per hour — present themselves to the world between midnight and dawn.

The researchers noted that if births were equally spaced out over 24 hours in a day, then 4.2 percent of babies would be delivered in each hour.

The data, collected from birth certificates in 41 states and the District, represent about 90 percent of U.S. births in 2013.

Other details of the study, “When Are Babies Born: Morning Noon or Night? Birth Certificate Data for 2013,” include:

* The Monday-to-Friday weekdays are the most popular for deliveries, compared with Saturdays or Sundays.

* The highest portion of all births — 6.3 percent and 6.0 percent, respectively — occurred between 8 a.m. and 9 a.m. and again from noon to 1 p.m.

* On weekdays after 5 p.m., the number of births per hour began a steady decline, reaching around 3 percent per hour around midnight.

* Women who gave birth without medical intervention were the most likely to give birth at any time of day or night.

* For women having a scheduled cesarean delivery, the most common hour of delivery (14.3 percent) the 8 a.m. hour. This was followed by the noon hour, with around 8 percent of those planned births happening at that time.

* The 2 percent of childbirths that occurred outside a hospital were most commonly completed in the afternoon and overnight hours, especially between 1 a.m. and 5 a.m.