A new study suggests that bending forward and walking extensively during early pregnancy may elevate the risk of miscarriage. The research, published in the journal Occupational and Environmental Medicine, analyzed data from nearly half a million women in Denmark.
Key Findings
Each additional hour of forward bending at a 30-degree angle within an eight-hour workday was associated with a 36% higher risk of miscarriage. Similarly, every extra hour of walking was linked to an 18% increased risk, while standing for an additional hour corresponded to a 3% higher risk.
The study examined 803,829 pregnancies among 475,312 women between 2004 and 2018. About one in ten pregnancies (81,307) ended in miscarriage, a rate lower than the typical 15% prevalence.
Methodology
Researchers from Bispebjerg Hospital in Copenhagen and the University of Copenhagen utilized a pregnancy-specific job exposure model. This model combined activity tracker readings with expert evaluations of time spent standing, walking, and forward bending at or beyond a 30-degree angle.
Limitations and Expert Comments
As an observational study, the findings cannot establish cause and effect. Limitations include a lack of individual data on smoking during pregnancy and potential confounding factors such as shift work or chemical exposures. Prof Asma Khalil, a consultant obstetrician at City St George’s, University of London, emphasized that the results should not be interpreted as meaning ordinary movement in early pregnancy is unsafe. She noted that while the study raises an interesting hypothesis, the findings require replication before they can inform precise workplace guidelines.
The researchers highlighted the importance of including early pregnancy in occupational health guidelines, stating that although mechanisms are not fully understood, these exposures may affect placental perfusion or hormonal regulation.
