Tammy Lee: 2.1PN Zygotes Can Be Viable and Deserve Separate Classification
Tammy Lee, Embryologist at Fertility North, shared a post on LinkedIn:
“2.1PN zygotes
Should we be using these atypically fertilised oocytes? What are their developmental and clinical outcomes? And how can we differentiate 2.1PNs from 3PNs?
I am incredibly proud to share our scoping review has been published online in Reproductive BioMedicine Online. This work was completed in collaboration with members of the Asia Pacific Initiative on Reproduction Embryology Special Interest Group.
In the paper we highlight:
- 2.1PN zygotes can be viable and if available, should undergo genetic testing for euploidy, ploidy status and biparental inheritance
- 2.1PN zygotes should be considered separately from 3PN zygotes
- There is currently no consistent definition of a 2.1PN zygote across the literature
To address this, we propose a working definition of a 2.1PN zygote and provide opinions to guide their use. We hope this review serves as a starting point for the standardisation of 2.1PN zygote classification and their use in both clinical and research settings.
I am so grateful to the ASPIRE Embryology SIG for the opportunity to collaborate and contribute to this important area of embryology.
Read the full paper available open access.”
Title: Clinical implications of zygotes showing 2.1 pronuclei: an ASPIRE Embryology Special Interest Group committee opinion
Authors: Tammy Lee, Diana Tain, T. Arthur Chang, Ryan Rose, Krishna Chaitanya Mantravadi, Lan Thi Thu Nguyen, Mi Kyung Chung, Keshav Malhotra, Kenji Ezoe, Sweelian Liow, Yanhe Liu
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