A 26 year-old woman presented with a left hemichorea while taking oral contraceptives (a combination of ethinyl-estradiol and norethisterone). There was marked improvement of the choreic movements after discontinuation of the oral contraceptive and complete resolution by 6 weeks. Induction of chorea is a rare complication of oral contraceptives. The possible mechanisms are briefly reviewed.
PIP: A left-handed 26-year-old woman was hospitalized in December 1984 for abnormal movements on the left side which had appeared abruptly 16 days earlier. Her medical history included neonatal anoxia with cyanosis and reanimation after a difficult delivery, and ophthalmic migraines. There were no previous rheumatismal or choreic episodes. The patient had taken a diphasic oral contraceptive (OC) containing 30 ng and 40 ng of ethinyl estradiol and 1 mg and 2 mg of norethisterone from 1976 to 1981 and had had a normal pregnancy and delivery in November 1983. In June 1984, 3 weeks after resuming use of the same pill, the patient began suffering violent migraines which persisted on a daily basis for 1 month. The abnormal movements of the left side were very broad at the outset. 3 days before hospitalization the OC was discontinued and the symptoms abated somewhat. On hospitalization, brusque, variable and arhythmic muscular jerks were visible on the face and left arm and leg. The left half of the body was hypotonic. The condition appeared to be hemichorea. A radioimmunologic test for synthetic steroid antihormone antibodies demonstrated the presence of anti-ethinyl estradiol antibodies at a level of 410 cpm, compared to the normal value of under 100 cpm. The electromyographic pattern was that of chorea. On discharge 12 days later the choreic movements had abated considerably after treatment with haloperidol 20 mg/day. 4 weeks after discontinuation of the OC and after discontinuation of the haloperidol, the abnormal muscular activity had disappeared; a neurologic examination 1 month later was normal. OCs have been proven responsible for some cases of chorea although the number of reported cases is small. Among hypotheses advanced to explain development of chorea are preexisting presence of unilateral lesions in the gray matter following a rheumatismal or viral episode or neonatal trauma which predisposes to a subsequent chorea induced by hormonal impregnation, or an immunologic action analogous to the mechanism of rheumatismal chorea.