Tamoxifen and pregnancy: an absolute contraindication?

  • T. N. Schuurman
  • P. O. Witteveen
  • E. van der Wall
  • J. L. M. Passier
  • A. D. R. Huitema
  • F. Amant
  • C. A. R. LokEmail author



Breast cancer is the most common malignancy among young women of reproductive age. Adjuvant treatment with tamoxifen reduces the risk of recurrence in hormone-sensitive breast cancer. However, the use of tamoxifen is considered contraindicated during pregnancy, because of a limited number of case reports demonstrating potential adverse effects on the fetus. The objective of this report is to give a more broad overview of the available data on the effect of tamoxifen exposure during pregnancy.


A literature review was performed using PubMed and the databases of the Netherlands Pharmacovigilance Centre Lareb and of the International Network on Cancer, Infertility, and Pregnancy.


A total of 238 cases of tamoxifen use during pregnancy were found. Of the 167 pregnancies with known outcome, 21 were complicated by an abnormal fetal development. The malformations described were non-specific and the majority of cases concerned healthy infants despite exposure to tamoxifen.


There seems to be an increased risk of fetal abnormalities when taking tamoxifen during pregnancy (12.6% in contrast to 3.9% in the general population), but the evidence is limited and no causal relationship could be established. The possible disadvantage of postponing or discontinuing tamoxifen for the maternal prognosis is unclear. Patients should be counseled about the use of tamoxifen during pregnancy instead of presenting it as being absolutely contraindicated.


Tamoxifen Breast cancer Pregnancy Teratogenicity Fetal toxicity 


Compliance with ethical standards

Conflict of interest

All authors declare that they have no conflict of interest.

Human and animal rights

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

Not applicable.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • T. N. Schuurman
    • 1
  • P. O. Witteveen
    • 2
  • E. van der Wall
    • 2
  • J. L. M. Passier
    • 3
  • A. D. R. Huitema
    • 4
    • 5
  • F. Amant
    • 1
    • 6
    • 7
  • C. A. R. Lok
    • 1
    Email author
  1. 1.Department of Gynecologic OncologyThe Netherlands Cancer Institute, Antoni van LeeuwenhoekAmsterdamThe Netherlands
  2. 2.Cancer CenterUniversity Medical Center UtrechtUtrechtThe Netherlands
  3. 3.Teratology Information ServiceNetherlands Pharmacovigilance Centre Lareb’s-HertogenboschThe Netherlands
  4. 4.Department of Pharmacy & PharmacologyThe Netherlands Cancer Institute, Antoni van LeeuwenhoekAmsterdamThe Netherlands
  5. 5.Department of Clinical Pharmacy, University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands
  6. 6.Department of Gynecologic OncologyAmsterdam University Medical CenterAmsterdamThe Netherlands
  7. 7.Department of OncologyCatholic University of LeuvenLeuvenBelgium

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