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Interferon beta-1b Pregnancy and Breastfeeding Warnings

Interferon beta-1b is also known as: Betaseron, Extavia

Interferon beta-1b Pregnancy Warnings

Animal studies have failed to reveal a teratogenic effect, but abortifacient activity has been demonstrated at higher than recommended doses. There are no controlled data in human pregnancy; however, spontaneous abortions were reported in 4 women during a trial for the treatment of multiple sclerosis. A report of a consensus conference was published in 1996. It states that interferon beta-1b is contraindicated in pregnant or nursing women or those who are actively attempting to become pregnant. Therapy should be stopped in patients who become pregnant while taking interferon beta-1b. It may be most prudent to start (or restart) therapy as soon as possible after delivery or weaning to help decrease the increased risk of exacerbations during the postpartum period. Findings of right incomplete double renal pelvis and ureter in a 1-year-old child is believed to be associated to the interferon therapy used by the mother up to 2.5 months before her pregnancy. FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

FDA pregnancy category: C Interferon beta-1b should not be used during pregnancy unless the potential benefit outweighs the potential risk.

See references

Interferon beta-1b Breastfeeding Warnings

A decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother. Excreted into human milk: Unknown Excreted into animal milk: Data not available Interferon beta has been used without apparent harmful effects in the nursing infant.

After using interferon beta-1b for multiple sclerosis throughout pregnancy, a woman continued the drug while exclusively breastfeeding her infant. Regular physician monitoring found the 5-month-old infant was developing well with no abnormalities.

See references

References for pregnancy information

  1. Watanabe M, Kohge N, Akagi S, et al. "Congenital anomalies in a child born from a mother with interferon-treated chronic hepatitis B." Am J Gastroenterol 96 (2001): 1668-9
  2. Lublin FD, Whitaker JN, Eidelman BH, Miller AE, Arnason BGW, Burks JS "Management of patients receiving interferon beta-1b for multiple sclerosis: report of a consensus conference." Neurology 46 (1996): 12-8
  3. "Product Information. Betaseron (interferon beta-1b)." Berlex, Richmond, CA.

References for breastfeeding information

  1. "Product Information. Betaseron (interferon beta-1b)." Berlex, Richmond, CA.
  2. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL:" ([cited 2013 -]):

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