[Sudden loss of consciousness during labour].

This case describes a 36-year-old woman, gravida 4 para 2 at 41 weeks and 3 days gestation, who appeared unconscious during labour for 75 minutes. After excluding physical disorders, it transpired that she was having a conversion disorder. A patient with a decreased level of consciousness in childbirth must be assessed using the ABCDE method, positioned in left lateral tilt to prevent inferior vena cava compression. After stabilization of the vital functions and establishing the patient's history, physical examination and laboratory tests are components of the initial clinical assessment. Neurological examination should focus on brainstem and bihemispheric pathology. If indicated, a brain CT, EEG and ECG should be performed. The diagnosis 'conversion disorder' can be supported by neurological examination, since the pattern of deficits usually does not conform to known anatomic pathways. In 37% of the cases, conversion disorder is preceded by physical stress or trauma. The prevalence in pregnant women is unknown. The first-line treatment is patient education.