Current Stem Cell Reports

, Volume 5, Issue 4, pp 125–132 | Cite as

The Impact of Mosaic Embryos on Procreative Liberty and Procreative Responsibility: Time to Put Innovative Technology on “Pause”

  • Shizuko TakahashiEmail author
  • Pasquale Patrizio
Ethics in Stem/Progenitor Cell Therapeutics (S Latham, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Ethics in Stem/Progenitor Cell Therapeutics


Purpose of Review

Preimplantation genetic testing for aneuploidy (PGT-A) is a controversial and an unvalidated procedure used for embryo screening and yet is being offered to patients undergoing in vitro fertilization (IVF). Recent media coverage of hundreds of normal euploid births from the transfers of “abnormal” mosaic embryos has brought increased social attention to this subject. Given the definition of normalcy is ambiguous, we must ask, is procreative responsibility enough to justify the disposal of mosaic embryos and to ask patients to start anew?

Recent Findings

A gradual change is seen in medical professionals giving patients the choice to transfer mosaic embryos, while patients are simultaneously becoming more aware of the false positives and reluctant to dispose potentially good embryos, hoping for self-repair.


The decision to intentionally transfer abnormal embryos may be an act of procreative liberty as well as a challenge to reproductive responsibility, but such burden placed on patients from a test prematurely commercialized to increase success rate is unethical. Innovative technologies must be properly validated to prevent further harm by false assumptions of the norm.


Mosaic embryo Procreative liberty Procreative responsibility PGT-A PGS Preimplantation genetic testing Ethics Reproductive medicine 



Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Biomedical Ethics, Graduate School of MedicineThe University of TokyoTokyoJapan
  2. 2.Department of Obstetrics and Gynecology, Graduate School of MedicineThe University of TokyoTokyoJapan
  3. 3.Yale Fertility CenterNew HavenUSA

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