A new study by City College London, University College London, and the National Childbirth Trust has identified 4am as the peak time for births.
The study, published in PLOS ONE, analysed five million births over a ten-year period in England.
The Time Births Are Most Likely To Happen
Babies born spontaneously were most likely to arrive between 1 am and 7 am.
Almost a third of the births occurred on weekdays, during working hours.
The remaining two thirds of births happened outside these hours and on weekends and public holidays.
As highlighted by the study, the time and day babies are born can vary, depending on whether labour begins spontaneously or via induction.
How the baby is born (for example, by c-section) was also found to have an impact on the time of the birth.
It is hoped the research will help hospitals to plan their staffing levels accordingly.
Spontaneous births following labour that started spontaneously (ie, no intervention) accounted for just over half of the births included in the study, and the babies were most likely to be born between 1 am and 6:59 am with a peak around 4 am. These births were also slightly more likely to happen on weekdays than on weekends.
C-sections accounted for 9.2% of births and these were most likely to occur between 9 am and 11:59 am on weekdays. Very few c-sections were performed outside normal office hours. This is not particularly surprising, as most planned c-sections are performed during the working week, and it is likely only emergency c-sections would be performed outside those hours.
Births following inductions account for just over a fifth of the births; these were most likely to occur around midnight from Tuesday to Saturday. This type of birth was less likely to occur on Sundays, Mondays and days immediately following public holidays.
The lowest numbers of births were recorded on Christmas Day and Boxing Day.
The researchers found the patterns of spontaneous birth hadn’t changed since the 1950s, but the rise in medical intervention has seen a change in the overall timing of births. The increasing rate of elective c-sections means more babies are now born on weekday mornings when elective c-sections are routinely performed.
Professor Alison Macfarlane, the senior author of the paper, and Professor of Perinatal Health at City, University of London, commented on the findings:
“It is known that obstetric intervention can influence the time of birth, but no previous analysis at a national level in England has yet investigated in detail the ways in which the day and time of birth varies by how labour starts and how women give birth.
“The research should be of interest to policymakers, as policies to increase community births may lower rates of obstetric intervention and affect these trends and impact on the overall timing of birth”.
Dr Peter Martin, a Lecturer in Applied Statistics at UCL (University College London) who conducted the research while at City, University of London, said:
“Long term experience and research from other areas has shown that human births without obstetric intervention are most likely to occur at night or in the early hours of the morning. This may be part of our evolutionary heritage. Our ancestors lived in groups that were active and dispersed during the day and came together to rest at night. So a night-time labour and birth probably afforded the mother and newborn baby some protection”.