Abnormal behavioral patterns in the human fetus at term: correlation with lesion sites in the central nervous system after birth.
We describe three fetuses at term that demonstrated abnormal behavioral patterns in utero when observed using real-time ultrasound. The abnormal patterns turned out to have neurologic correlations after birth. In case 1, despite a normal breathing pattern, no movement in any of the four extremities was observed, thus suggesting the existence of a spinal cord lesion at the rostral end, located at C4 or C5. In case 2 a lack of breathing movement was noted repeatedly, together with the abnormal finding that alternation of periods of rapid eye movement (REM) sleep with those of non-rapid eye movement (NREM) sleep was not present. These findings implied a lesion involving the pons and/or medulla oblongata. In case 3 movement of the four extremities, breathing movement, and alternating periods of REM sleep and NREM sleep were found to be within the normal range. The concurrence of regular mouthing and the NREM sleep period was not observed, however, suggesting impairment in the brain function responsible for NREM sleep located from the pons through the thalamocortical connection to the cerebral hemisphere.