A new study has linked bending forward at work during early pregnancy to a significantly higher risk of miscarriage. The research also suggests that prolonged walking and standing may increase the risk.
Study Details
The study analyzed data from 2004 to 2018, encompassing over 800,000 pregnancies among 475,312 women in Denmark. Researchers used a pregnancy-specific job exposure model that combined activity tracker readings and expert evaluations of time spent standing, walking, and bending forward at a 30-degree angle.
Of the pregnancies studied, 81,307 (just over one in ten) ended in miscarriage. The analysis revealed that standing, walking, and bending forward were all associated with a higher risk of miscarriage.
Key Findings
- Each additional hour spent bending forward at a 30-degree angle carried a 36% higher risk of miscarriage.
- Each additional hour spent walking was linked to an 18% higher risk.
- Each additional hour spent standing was associated with a 3% higher risk.
Risks were greater among women who had been off work in the previous weeks compared to those who had not been absent. In the UK, early miscarriages (within the first 12 weeks) affect between 10% and 20% of pregnancies.
Implications and Recommendations
Researchers stressed that further studies are needed but noted that the findings, published in the journal Occupational & Environmental Medicine, “highlight the importance of including the early pregnancy stage into guidelines for pregnant workers.”
They added: “If the observed effects are true, they support a recommendation to reduce occupational standing, walking and forward bending during early pregnancy. However, given the anticipated residual confounding and uncertainties in the highest exposure levels, our findings may be too restricted.”
The authors emphasized the need for replication in similar populations, incorporation of smoking status and other maternal health information, and further trend analyses and meta-analyses to establish exposure-response relationships and identify potential threshold levels.
