Movies are available at the press of a button. Your online order can show up at your doorstep within hours. The rideshare driver comes at a moment’s notice.
It seems like everything in our lives is available when we want it — and research shows our on-demand ways may (very literally) start at birth.
More than ever, births are being scheduled through C-sections or by inducing labor at a specific time. Ohio State economics professor Jay Zagorsky has some insight as to why it’s happening.
“This shift from unscheduled births to setting birth times is unparalleled in history,” Zagorsky said.
Starting in 2003, states across the United States began switching to a new standardized birth certificate that gathers more information than they had before. Part of the extra information is the exact time of day when each child was born.
This table (Figure A) shows the time and day when babies were born, taken from the seven most recent years of publicly released information.
There is no reason to expect that babies prefer leaving the womb on any particular day of the week. This means that births should be roughly evenly spaced throughout the week. However, the table’s shaded gray bottom row shows this even spacing doesn’t happen.
Instead, only 20 percent of all babies are born on Saturday or Sunday. If births were evenly distributed, about 29 percent (two days out of seven) of all births should occur on the weekend.
If babies were born evenly spaced during the day, each of the table’s four time slots should have about 25 percent of all births.
However, the shaded gray column on the far right shows far more babies than expected are born between noon and 6 p.m. Interestingly, the midnight to 6 a.m. time frame is now the least likely period for a baby to be born, capturing only 16.7 percent of all births.
This is a far cry from a 1972 review that found the early morning hours were the most likely time for women to give birth.
The least likely time for a baby to be born, shaded in green, is very early Monday morning.
The yellow numbers in the center of the table show the most likely time for a baby to be born is Tuesday afternoon, closely followed by Wednesday and Thursday afternoons.
Births today are more likely by C-section or induction.
The percentage of women who give birth by C-section has dramatically increased over time.
Since only about one-quarter of all women who undergo a C-section did a trial of labor, this indicates many C-sections are scheduled. C-sections may be scheduled by the doctor, or by the mother, or as emergency procedures. Unfortunately, birth records don’t indicate why a C-section was performed.
The same trend occurred for births that were induced. In 1990, about 10 percent of all women giving birth were induced, but by 2015 the share had more than doubled to almost 24 percent.
Vaginal births happen more or less evenly spaced out during the day, with a slight bump in the early morning hours. C-section births typically happen either around 8 a.m. or noon. Induced deliveries typically happen around 3 p.m.
There are many potential reasons for the increases in C-sections and inductions.
Examples range from improved medical imaging that lets doctors determine with more accuracy uterine and fetal conditions during the last few weeks of pregnancy to a desire by doctors to avoid any type of problem to either the mother or unborn child.
However, scheduling to meet the convenience of doctors and other medical staff is likely one factor driving this shift in birth times.
Data on when doctors and other medical professionals work show the vast majority are currently on the job from 8 a.m. to 4 p.m. Relatively few work during the wee hours of the night and early morning.
The shift from vaginal childbirth to C-section or induction has moved more babies from being born in the middle of the night to times more closely aligned with health care workers’ daily schedules.
Research suggests that when doctors and patients have an opportunity to decide when to schedule a birth, the doctors’ preferences win out about three-quarters of the time, possibly because doctors value their leisure.
Scheduling by mothers might be a contributing factor.
Research has found that some Chinese mothers appear to be scheduling their sons’ births to avoid unlucky days and ensure a lucky birthday. Tax implications also have a small impact on births around New Year’s Eve.
The March of Dimes, a nonprofit devoted to preventing birth defects, is concerned about scheduling; it runs a campaign asking mothers to wait until 39 weeks before giving birth. The National Institutes of Health convened an expert panel that estimated 2.5 percent of all births in the United States are cesarean deliveries done on maternal request, but cautioned that it has “little confidence in the validity of these estimates.”
There is research that suggests it is more dangerous to have a baby in the middle of the night, when less medical staff is available. But the actual riskiness of vaginal childbirth, C-section or induced delivery is affected by a whole host of factors depending on the mother’s, child’s and hospital’s characteristics.