title: The occurrence of unblocked segments during continuous lumbar epidural analgesia for pain relief in labour.
mesh_terms: D000767:Anesthesia, Epidural / Q000009:adverse effects*; D000773:Anesthesia, Obstetrical / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008022:Ligaments / Q000294:innervation; D009119:Muscle Contraction; D011247:Pregnancy