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[Possible teratogenic effects of thiamazole]

H M Ozgen1, M H Ozgen, W E Reuvers-Lodewijks

  • 1Academisch Medisch Centrum/Universiteit van Amsterdam, afd. Kindergeneeskunde, Meibergdreef 9, 1105 AZ Amsterdam.

Nederlands Tijdschrift Voor Geneeskunde
|January 31, 2006
PubMed

Insights

Maternal thiamazole use during early pregnancy may cause congenital anomalies like choanal atresia and developmental delays in newborns. Propylthiouracil is recommended as a safer alternative for treating hyperthyroidism during pregnancy.

Area of Science:

  • Endocrinology
  • Teratology
  • Neonatology

Background:

  • Hyperthyroidism in pregnant women requires careful management to prevent adverse fetal outcomes.
  • Thiamazole is a medication used to treat hyperthyroidism.

Observation:

  • A male infant presented with choanal atresia, dysmorphic facial features, and delayed speech and language development.
  • The infant's mother used thiamazole during the first trimester of pregnancy for hyperthyroidism.

Findings:

  • Maternal thiamazole exposure during early pregnancy is a potential cause of congenital anomalies, including choanal atresia and developmental delays.
  • This case aligns with previously described embryopathy linked to maternal thiamazole use, characterized by choanal atresia, esophageal atresia, dysmorphic features, growth retardation, and psychomotor delays.

Implications:

  • Propylthiouracil is identified as the preferred treatment for hyperthyroidism during pregnancy due to a lack of associated embryopathy.
  • Thiamazole should be reserved for pregnant patients or those planning pregnancy only when propylthiouracil is contraindicated.

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