Pregnancy outcome after gestational exposure to amiodarone in Canada

Am J Obstet Gynecol. 1995 Apr;172(4 Pt 1):1307-11. doi: 10.1016/0002-9378(95)91498-6.


Objective: Our purpose was to quantitate the risk of perinatal thyroid dysfunction and other amiodarone-induced adverse effects among infants exposed in utero to amiodarone.

Study design: A historic cohort study of gestational exposure to amiodarone was conducted by contacting Canadian cardiac electrophysiologists.

Results: Twelve cases were identified. Of six with first-trimester exposure, one child had congenital nystagmus with synchronous head titubation. There was one case each of transient neonatal hypothyroidism (9%) and hyperthyroidism (9%). A fourth child, exposed to amiodarone from 20 weeks' gestation, had developmental delay, hypotonia, hypertelorism, and micrognathia. Four small-for-gestational-age infants were also exposed to beta-blockers, which in addition to maternal cardiac disease, have been recognized to cause growth restriction. beta-Blockers may also have contributed to bradycardia in one of the three fetuses in whom this was observed.

Conclusions: Gestational exposure to amiodarone may be complicated by perinatal hypothyroidism or hyperthyroidism and possibly neurologic abnormalities, intrauterine growth retardation or fetal bradycardia. Concomitant beta-blocker therapy should probably be avoided. Full neonatal thyroid function tests and developmental follow-up are recommended.

MeSH terms

  • Adrenergic beta-Antagonists / adverse effects
  • Adult
  • Amiodarone / adverse effects*
  • Arrhythmias, Cardiac / drug therapy*
  • Bradycardia / chemically induced
  • Canada
  • Cohort Studies
  • Female
  • Fetal Diseases / chemically induced
  • Fetal Growth Retardation / chemically induced
  • Humans
  • Hyperthyroidism / chemically induced
  • Hypothyroidism / chemically induced
  • Infant, Newborn
  • Nervous System Diseases / chemically induced
  • Pregnancy
  • Pregnancy Complications, Cardiovascular / drug therapy*
  • Pregnancy Outcome*
  • Prenatal Exposure Delayed Effects*
  • Retrospective Studies
  • Risk Factors


  • Adrenergic beta-Antagonists
  • Amiodarone