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Related Experiment Video

Updated: Mar 31, 2026

Generation of Dispersed Presomitic Mesoderm Cell Cultures for Imaging of the Zebrafish Segmentation Clock in Single Cells

Generation of Dispersed Presomitic Mesoderm Cell Cultures for Imaging of the Zebrafish Segmentation Clock in Single Cells

Published on: July 24, 2014

Developmental clock compromises human twin model created by embryo splitting.

Laila Noli¹, Yaser Dajani¹, Antonio Capalbo²

¹Division of Women's Health, Faculty of Life Sciences and Medicine, King's College London and Assisted Conception Unit, Guys' Hospital, London SE1 9RT, UK.

Human Reproduction (Oxford, England)

|October 23, 2015

Summary

Human embryos created by in vitro twinning are not suitable for clinical use or research. These twin embryos show delayed development and poor quality compared to those from in vitro fertilization.

Keywords:

blastocyst cleavage stage human embryos developmental clock embryo splitting monozygotic twins morphokinetics

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Generation of Dispersed Presomitic Mesoderm Cell Cultures for Imaging of the Zebrafish Segmentation Clock in Single Cells

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Published on: August 10, 2022

Area of Science:

Reproductive biology
Developmental biology
Embryology

Background:

In vitro twinning of human embryos has shown limited success in primates, unlike in animals.
Previous studies suggest potential viability of split human embryos, but qualitative analysis is scarce.

Purpose of the Study:

To compare the quality of in vitro-generated human twin embryos with those created through in vitro fertilization (IVF).

Main Methods:

Comparative analysis of 176 twin embryos (from 88 split human embryos) and 42 IVF embryos.
Morphokinetic and developmental competence assessment of embryos at cleavage stages.

Main Results:

Twin embryos exhibited delayed inner cell mass (ICM) differentiation and poor ICM quality.
Majority of cells in twin embryos expressed both ICM and trophectoderm markers simultaneously.
Embryo size in twins correlated with the number of cells used for creation, influenced by a 'developmental clock'.

Conclusions:

In vitro-generated human twin embryos are unsuitable for clinical applications.
These embryos are also not recommended for research purposes due to developmental abnormalities.
Blastomere separation for twinning may be limited by developmental timing, unlike blastocyst bisection.