Persistence of back pain symptoms after pregnancy and bone mineral density changes as measured by quantitative ultrasound--a two year longitudinal follow up study.

Background: Previous research has shown a loss of bone mineral density (BMD) during pregnancy. This loss has been correlated to the occurrence of back pain symptoms during pregnancy. The objective of this study was to evaluate whether persistence of back pain symptoms 2 years after pregnancy could be associated with BMD changes as measured by quantitative USG of the os calcis.