Births: the weekly cycle

Background, including element of originalityIt is known that obstetric intervention can influence the timing of birth but there are few studies investigating how the day of birth is associated with the onset of labour and the... [ view full abstract ]

Background, including element of originality

It is known that obstetric intervention can influence the timing of birth but there are few studies investigating how the day of birth is associated with the onset of labour and the mode of giving birth.

Method

As part of a project to analyse the timing of birth and its outcomes  we linked data from birth registration, birth notification, and Maternity Hospital Episode Statistics, to analyse data for over 5 million births in NHS maternity units in England from 2005 to 2014.   To analyse the association between the day of the week of birth and the onset of labour and mode of giving birth by gestational age, we fitted negative binomial regression models to the daily frequency of births, controlling for seasonal cycles of births as well as trends over time.

Results

The numbers of births varied considerably by onset of labour and mode of giving birth.  Births after spontaneous onset and spontaneous birth are slightly more likely to occur on weekdays than at weekends or on public holidays . Elective caesarean births are concentrated onto weekdays. Births following induced labours are more likely to occur on Tuesdays to Saturdays and on days before a public holiday period, than on Sundays, Mondays or during or just after a public holiday.

Discussion

Numbers of births per day vary by care pathway, and these patterns have implications for midwifery and medical staffing. The timing of intervention is partly determined by the staffing arrangements of maternity units and availability of facilities, such as theatres. It may be that the lower numbers of term births without intervention at weekends and on holidays could arise from selective intervention in preceding days.

Conclusion

While there is a rationale for arranging managed care on weekdays, maternity services need to ensure appropriate staffing at all times, taking into account day to day variation in activity.