Heavy lifting at work and risk of genital prolapse and herniated lumbar disc in assistant nurses

Lifting of heavy burdens increases the intra-abdominal pressure, and may induce an increased risk of prolapse of the female internal genitals. While taking care of patients, the nursing staff in hospitals and nursing homes are exposed to heavy lifting. Scientifically uncontrolled causal observations among assistant nurses gave rise to the assumption of an increased risk. To test this hypothesis, a register study was carried out to investigate the risk of genital prolapse among assistant nurses compared with the female Danish population in general. For validation, the incidence of operation due to herniated lumbar disc was investigated. Two registers were used for the analyses, a pension fund register and the Danish National Registry of Hospitalized Patients. Some 28,619 assistant nurses, aged 20-69 years, and 1,652,533 controls of similar age were included. Operations due to genital prolapse and herniated lumbar disc were recorded during one year. The odds ratio (OR) with 95 per cent confidence intervals for the risk of operation due to genital prolapse was significantly increased among assistant nurses, OR = 1.6 (1.3-1.9), P < 0.0001. Correspondingly, the risk of operation for herniated lumbar disc was significantly increased for assistant nurses, OR = 1.6 (1.2-2.2), P < 0.01. We conclude that operations due to genital prolapse are more common among assistant nurses than among the overall female population. Based on this finding, we hypothesize that heavy lifting at work may be the underlying cause. This study confirmed the suggestion of previous epidemiological studies that herniated lumbar disc is associated with heavy lifting at work.