Delivery of healthy babies after natalizumab use for multiple sclerosis: a report of two cases

Acta Neurol Scand. 2011 Jun;123(6):430-3. doi: 10.1111/j.1600-0404.2010.01426.x. Epub 2010 Sep 16.


Background: In current literature, no data on safety in pregnancy for new drugs in the treatment of multiple sclerosis (MS) like natalizumab (Tysabri®), a humanized monoclonal antibody against α4 integrins, are yet available. In the management of MS, natalizumab is the first monoclonal antibody approved to the market.

Methods: We describe the pregnancy and outcome in two women with MS using natalizumab. The first patient used it in the periconceptional period, and the second patient used it in both the periconceptional period and throughout gestation.

Results: The antenatal course of the first patient was complicated by an exacerbation of MS. The second patient did not experience MS relapses during pregnancy, while still using natalizumab. The newborns did not show any abnormalities postnatal and at 6 weeks' follow-up.

Conclusions: This is the first detailed report on pregnancy and delivery of two babies after maternal treatment of MS with natalizumab. From the small number of cases on the usage of natalizumab during pregnancy in literature, we cannot conclude whether the use of natalizumab is safe, and long-term effects are not known. Further research is needed to establish the exact effects on pregnancy and intrauterine development as well as the long-term effects. Prenatal counseling with thorough explanation of the risks and careful decision making is advisable.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Antibodies, Monoclonal, Humanized / administration & dosage*
  • Antibodies, Monoclonal, Humanized / adverse effects*
  • Apgar Score
  • Female
  • Humans
  • Immunologic Factors / administration & dosage*
  • Immunologic Factors / adverse effects*
  • Infant, Newborn
  • Integrin alpha4 / immunology
  • Multiple Sclerosis / drug therapy*
  • Multiple Sclerosis / immunology
  • Natalizumab
  • Pregnancy
  • Prenatal Exposure Delayed Effects
  • Secondary Prevention
  • Treatment Outcome


  • Antibodies, Monoclonal, Humanized
  • Immunologic Factors
  • Natalizumab
  • Integrin alpha4