Miscarriage risk 'increased' by working night shifts
Pregnant nurses and midwives may be able to reduce their risk of miscarriage by not working night shifts, suggests research showing more than a quarter of miscarriages could be prevented.
Researchers carried out a nationwide study in Denmark looking at a range of lifestyle factors, including work schedule, which could potentially be altered to reduce miscarriage risk.
Those identified included being obese or underweight, being aged 30 or over at conception, lifting weights of more than 20 kilograms a day, alcohol consumption and working night shifts.
The study – published in BJOG: An International Journal of Obstetrics and Gynaecology – estimated 25.2% of miscarriages might be prevented by reducing all these risk factors to low levels, although the most significant were maternal age and alcohol intake.
Denise Linay, head of organising and engagement at the Royal College of Midwives, said the findings around shift patterns were of particular interest.
“Things like alcohol and being overweight have been discussed long and hard,” she said. “But the interesting thing here is the issue of working shifts. We know working nights can have an adverse impact on health, yet employers have to cover 24-hour services.”
She said employers had a responsibility to look after pregnant staff, and should try and accommodate requests to change shifts. But she noted this would impact on other staff who may not want to take on more night work in covering for them.
“At lot of miscarriages take place before 12 weeks and most people won’t want to tell their employer that early on,” she said. “Once an employer knows someone is pregnant they will complete a risk assessment that may identify they’re doing night shifts and suggest they may be better off doing days.”
She suggested the risks associated with lifting heavy weights would be reduced by stringent safety rules around manual handling.
The study used data from more than 91,400 pregnancies included in the Danish National Birth Cohort between 1996 and 2002. Of these 3,177 resulted in miscarriage.
Caroline Overton, a spokeswoman for Royal College of Obstetricians and Gynaecologists, described the study as “very interesting”. “It’s fantastic to have such a big study that re-iterates health advice we have already been promoting to pregnant women,” she said.
But she stressed it must be read in the context of other studies and that more detailed research was needed.
- Read the full paper BJOG: An International Journal of Obstetrics and Gynaecology