Page 54 - ESHRE2019

Mosaicism in ongoing pregnancies
Confined placental mosaicism
❑ CPM may be a numerical or a structural chromosomal abnormality
❑ It may be non-mosaic or mosaic
❑ It may concern all or some of the chorionic villi (cytotrophoblast / mesenchymal core)
Cytotrophoblast
Mesenchymal core
CPM can therefore be classified into three types:
• Type 1 CPM (50%): cytotrophoblast (STC-villi) – Mitotic origin ++
• Type 2 CPM (40%): mesenchymal core (LTC- villi)
– Mitotic origin ++
• Type 3 CPM (10%): cytotrophoblast +
– Meiotic origin ++
(Wolstenholme, 1996)
mesenchymal core
Short-term culture
Long-term culture
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