title: Pregnancy and fetal outcomes following natalizumab exposure in pregnancy. A prospective, controlled observational study.
abstract: BACKGROUND
  Safety data on first-trimester natalizumab exposure are scarce, as natalizumab is usually withdrawn three months before pregnancy.
  
  
  OBJECTIVE
  The objective of this paper is to investigate the fetal safety of exposure to natalizumab (Tysabri(®)) during the first trimester of pregnancy using disease-matched (DM) and healthy control (HC) comparison groups.
  
  
  METHODS
  A total of 101 German women with RRMS exposed to natalizumab during the first trimester of pregnancy were identified. Birth outcomes in the exposed group were compared to a DM group (N = 78) with or without exposure to other disease-modifying drugs, and an HC group (N = 97).
  
  
  RESULTS
  A total of 77, 69 and 92 live births occurred in the Exposed, DM and HC groups, respectively. The rates of major malformations (p = 0.67), low birth weight (<2500 grams) (p = 1.0) and premature birth (p = 0.37) did not differ among groups. Higher miscarriage rates (p = 0.002) and lower birth weights (p = 0.001) occurred among the Exposed and DM groups, as compared to the HC; however, there was no significant difference between the Exposed and DM groups.
  
  
  CONCLUSIONS
  Exposure to natalizumab in early pregnancy does not appear to increase the risk of adverse pregnancy outcomes in comparison to a DM group not exposed to natalizumab.
authors.affiliation: Motherisk Program, Division of Pharmacology and Toxicology, The Hospital for Sick Children, Canada/University of Toronto, Leslie Dan Faculty of Pharmacy, Canada neda.ebrahimi@sickkids.ca.
authors.forename: Neda
authors.initials: N
authors.lastname: Ebrahimi
authors.affiliation: St. Josef Hospital, Faculty of Medicine, Ruhr University, Germany.
authors.forename: Sandra
authors.initials: S
authors.lastname: Herbstritt
authors.affiliation: St. Josef Hospital, Faculty of Medicine, Ruhr University, Germany.
authors.forename: Ralph
authors.initials: R
authors.lastname: Gold
authors.affiliation: MS Comprehensive Care Center USC, Keck School of Medicine, USA.
authors.forename: Lilyana
authors.initials: L
authors.lastname: Amezcua
authors.affiliation: Motherisk Program, Division of Pharmacology and Toxicology, The Hospital for Sick Children, Canada/University of Toronto, Leslie Dan Faculty of Pharmacy, Canada.
authors.forename: Gideon
authors.initials: G
authors.lastname: Koren
authors.affiliation: St. Josef Hospital, Faculty of Medicine, Ruhr University, Germany.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Hellwig
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000009:adverse effects*; D007231:Infant, Newborn; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy*; D000069442:Natalizumab / Q000009:adverse effects*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000188:drug therapy*; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First / Q000187:drug effects
chemical_list: D007155:Immunologic Factors; D000069442:Natalizumab
keywords: Multiple sclerosis; fetal safety; natalizumab; pregnancy exposure