Back pain in pregnancy - Magnetic resonance imaging correlation

AIM: To study the relationship of disk abnormality and signal changes of the uterine cervix on magnetic resonance imaging (MRI) with back pain in pregnancy at 36-39 weeks of gestation. MATERIAL AND METHODS: One hundred and five pregnant Chinese women with previous Caesarean section at 36-39 weeks gestation undergoing magnetic resonance pelvimetry performed for a study for trial of vaginal delivery were questionnaired for back pain. Sagittal T2-weighted images were analysed for intervertebral disk abnormality, and signal intensity of the uterine cervix on the same sagittal images. The findings on MRI were correlated with back pain. RESULTS: Seventy-three (70%) of the pregnant women had back pain. Disk bulge or prolapse were infrequent but correlated significantly with the presence of back pain (P = 0.02). Women with back pain in the current pregnancy tended to have a higher signal intensity of the uterine cervix compared with those without (P = 0.006). Women with a history of back pain also had higher cervical signal intensity compared with those without (P = 0.02). CONCLUSION: Disk bulge or prolapse was associated with back pain in pregnancy but were relatively infrequent. The significant correlation of high signal intensity in the uterine cervix and back pain suggested that soft tissue laxity may be a more important cause of back pain in pregnancy than disk bulge or prolapse.