Friday November 9 2012
Fatigue is a common cause of sick leave when pregnant
The Daily Mail reports that pregnant women take ‘at least two months sick leave’ from work, but fails to mention that the study they report on looks at Norwegian women.
In the study, the researchers asked women how much sick leave they had taken during pregnancy and took detailed pregnancy-related information, recent medical and mental health history, socio-demographics and lifestyle and behavioural factors.
Overall, they found that 75% of the women had taken sick leave at some point during pregnancy, and the most common time for taking sick leave was the third trimester, from 29 weeks onwards, when 63% of the study sample had taken leave.
The main reasons for taking sick leave were:
- pelvic girdle pain
- nausea and vomiting
An important point to be aware is that we do not know that a similar pattern would be found in the UK. Also it is not possible to demonstrate direct cause and effect between the many other socioeconomic, lifestyle (including working life) and medical/mental health factors that the research associated with sick leave
Still, the study demonstrates that while pregnancy is not an illness, it can impact on women’s health and wellbeing. The study may help health professionals and policy makers to further understand the reasons that pregnant women may take time off of work and consider solutions, e.g. encouraging flexible working practices for pregnant women who work.
Read more advice about working during your pregnancy
Where did the story come from?
The study was carried out by researchers at Stavanger University Hospital, Norway and was funded by the Norwegian Research Council.
The study was published in the peer-reviewed British Journal of Obstetrics and Gynaecology.
The information contained in the Mail’s report of the study is generally accurate, though it is not apparent why they headline the study as being ‘controversial’. Also, it is not until around two-thirds of the way through the story that the paper makes clear that these findings probably do not apply to pregnant women in the UK.
What kind of research was this?
This was analysis of data from a cohort study exploring what proportion of pregnant women take sick leave during pregnancy in Norway, and the reasons for doing so.
This involved giving women questionnaires at two routine antenatal check-ups and then exploring any factors that were associated with them having time off.
This reasonably large study can’t tell us much more than how common it is for Norwegian women to take sick leave in pregnancy. Though the factors associated with sick leave are of interest, the study can’t prove any direct link between these factors and the reason for work absence.
The authors say that population-based information such as this may help to guide clinicians and policy makers in Norway on how to handle requests for, and possibly reduce, sick leave during pregnancy.
What did the research involve?
This study involved participants of the Akershus Birth Cohort, which is an ongoing study of women scheduled to give birth at Akershus University Hospital in Norway. Recruitment was between 2008 and 2010, and all women were approached when they underwent routine ultrasound scans at 17 weeks of pregnancy.
A total of 3,752 women agreed to complete a questionnaire at 17 weeks (81% of those asked), and 81% of these women also agreed to complete a second questionnaire at 32 weeks.
The final sample included 2,918 women who had completed both questionnaires and had completed information on the main outcome of interest – sick leave.
At 32 weeks, women were asked if they had ever been sick during pregnancy. If they answered yes they were asked in which trimester of pregnancy, for how many weeks and for what reason.
The reasons were grouped into the following catogories:
- fatigue/sleep problems
- back pain
- pelvic girdle pain
- complications related to pregnancy – such as gestational diabetes
- and ‘other’ (miscellanous reasons)
The women were also asked whether their work situation had been adjusted to accommodate for their pregnancy and if not, why not, with options of:
- non-strenuous work
- impossible or nearly impossible – due to the nature of the role (for example, if your job involves driving a bus there is little an employer can do to change the work situation)
- it was difficult to ask
- I have asked but the request was not granted
Extensive information was collected in the two questionnaires at 17 and 32 weeks on demographics, past reproductive history (such as details of previous pregnancies), any fertility problems, information on the current pregnancy and lifestyle behaviour. Validated scales were also used to assess insomnia and depression symptoms. The researchers looked at whether any of these factors were associated with the likelihood of a woman taking sick leave.
What were the basic results?
Of the 2,918 women, 75% had taken sick leave at some point during their pregnancy up to 32 weeks; 20% had taken no sick leave at all up until then; and 5% were not in paid work.
When looking at which trimester of pregnancy that sick leave was taken:
- 29% reported taking leave in the first 12 weeks of pregnancy
- 39% in the second trimester between 13 and 28 weeks
- 63% had taken leave in the third trimester from 29 weeks onwards (the trimester that they were currently in when they were asked about sick leave at 32 weeks)
Half of the women who took sick leave took 8 weeks or less.
The reasons reported for sick leave were:
- fatigue/sleep problems 34.7% of women
- pelvic girdle pain 31.8%
- nausea/vomiting 23.1%
- lower back pain 17.7%
- pregnancy complications 9.2%
- anxiety or depression 2.1%
- other reasons 23.8%
The following self-reported factors were significantly associated with increased risk of taking sick leave in pregnancy:
- younger age
- pregnancy sickness (nausea/vomiting)
- not taking weekly exercise in early pregnancy (before 17 weeks)
- reporting chronic pain problems before or
- during pregnancy
- having had fertility treatment
- having conflicts in the workplace
- having had one or more previous pregnancies
- previous depression
- having no higher education
- having insomnia in the third trimester
Generally most of the same factors were associated with sick leave when looking at specifically the first and second trimesters. In the third trimester, pelvic girdle pain and back pain were also associated with sick leave.
Sixty per cent of women reported having some adjustment of their work situation made for them during pregnancy. The main reason given for work not being adjusted among women who took sick leave was that it was ‘impossible or nearly impossible’ (44.2%).
How did the researchers interpret the results?
The researchers conclude that most women take sick leave during pregnancy. They suggest that previous medical and mental health history, work conditions and socio-economic factors need to be addressed to better understand the reasons for taking sick leave during pregnancy.
This is an interesting study that benefits from including a large sample of women due to give birth in Norway and collecting detailed information on various socio-demographic details, medical and pregnancy-related history and lifestyle behaviour. The study demonstrates how common it is for women to take some sick leave during pregnancy – 75% had taken some sick leave by 32 weeks of pregnancy.
However, there are some important points to consider:
- Although the women were followed over time, the analyses were essentially cross-sectional, as women were questioned on leave taken during their pregnancy and also asked about various other factors that they were experiencing around the time of pregnancy, without establishing which came first. Other unknown or unmeasured factors may also be influencing the associations seen. This means that it is not possible to say whether the factors assessed could have directly contributed to the women’s sick leave, only that they are associated with sick leave.
- Sick leave and the potentially associated factors were assessed by self-report on a questionnaire, so there may have been some inaccuracies.
- Though the study included a large sample of 2,918 women, this in fact represents only 47% of 6,244 women who were approached to take part in the study at 17 weeks. Compared to women who took part, those who did not participate in the study were significantly younger, more often had more children, had lower educational level, and more often had symptoms of depression at 17 weeks of pregnancy. Therefore, the study sample may not be entirely representative of the general population of pregnant women, and it is possible that those who did not take part may have had a different prevalence of pregnancy sick leave.
- The study is of Norwegian women and we don’t know what findings would be seen in a sample of pregnant UK women.
Overall, this reasonably large study tells us how common it is for Norwegian women to take sick leave during pregnancy. The authors say that population-based information such as this, about the factors associated with sick leave in pregnancy, may help to guide clinicians and policy makers in Norway on how to handle requests for and possibly reduce sick leave during pregnancy.
But due to the differences between Norway and the UK there is not much this study can tell us about how much time UK pregnant women take off work. A similar study would need to be run in this country.
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on twitter.