Purpose: To determine the prevalence of low back pain in pregnant women and to describe its characteristics and associated factors.
Methods: The participants were 269 pregnant women in the first to the third trimester of pregnancy, seen at the obstetrics outpatient clinic of a University Hospital in the Brazilian Northeast. We applied a questionnaire in order to obtain data regarding socio-demographic variables, obstetric history and characteristics of low back pain, as well as the Oswestry and Rolland Morris questionnaires to assess disability and a visual analog pain scale to measure pain intensity.
Results: The prevalence of low back pain was 73%, with the following characteristics: stabbing (62/31.6%), irradiation (162/82.6%), of daily frequency (105/53.5%), usually starting at night (83/42.3%) when it was also more intense (122/62.2%), and lasting about 1 hour in 118 women (60.2%). Pain improved with rest (100/51%), worsened when the women stood or sat for a long time (86/43.9%) and when they did housework (85/43.4%). The level of disability ranged from "mild" to "moderate" in most cases. Urinary tract infection (p=0.02) and the scores of the Oswestry and Rolland Morris questionnaires showed significant association with the visual analogue pain scale.
Conclusion: The prevalence of back pain among pregnant women is high, with varying characteristics. The degree of disability is usually moderate and the presence of urinary infection and higher disability scores were associated with greater intensity of low back pain.