Zeynab Kazemianpour: 2 Unusual Oocytes Observed Before ICSI
Zeynab Kazemianpour, Clinical Embryologist at Nikan Hospital, shared on LinkedIn:
”Two unusual oocytes observed before ICSI
Today, I came across two very different oocytes during denudation.
One was already degenerated and had an abnormal, dark appearance, making it unsuitable for ICSI.
The other was quite different. Before any sperm injection, the oocyte had already started to cleave, showing a morphology similar to an early embryo. In our lab, we refer to these as parthenogenetic oocytes.
This made me think about how differently oocytes can respond even before the ICSI procedure begins.
What could be behind these observations?
For oocyte degeneration, possible contributing factors include:
- Oocyte quality and cytoplasmic abnormalities
- Mechanical stress during denudation
- Exposure to hyaluronidase
- Temperature or pH fluctuations
- Delayed handling after oocyte retrieval
- Other patient- or cycle-related factors
For spontaneous parthenogenetic activation, possible mechanisms include:
- Spontaneous oocyte activation
- Abnormal Ca²⁺ oscillations
- Cytoplasmic or oocyte maturity-related factors
- Mechanical or chemical stimulation
Of course, a single observation cannot tell us exactly what caused either event. But these unexpected findings are a good reminder that every oocyte can behave differently, and even small changes in the laboratory environment or handling process may matter.
Have you ever observed parthenogenetic cleavage before ICSI in your lab?
I’d be interested to hear how often you see it and what factors you think may contribute to it.”

Stay informed with the latest updates in fertility and reproductive medicine on Fertility News.
-
Sep 4, 2026, 17:17Dan Annetts: The Fabulous CREATE Fertility Bristol Team This Week
-
Sep 4, 2026, 17:15Arsiak Vartenian: The Question I Wish Fertility Clinics Asked Women More…
-
Sep 4, 2026, 17:11Saff Mitten: Do You Ever Worry Your Friends Are Getting Bored of Your Long IVF Journey?
-
Sep 4, 2026, 17:04David Pening: New Article on the Genetic Landscape of Acephalic Spermatozoa Syndrome
-
Sep 4, 2026, 16:55Blessed Obediran: The Science of Donor Conception Is Easy, The Harder Questions Are the Ethical Ones
-
Sep 4, 2026, 16:51Delighted to Welcome a Team of Colleagues from St. Gallen, Switzerland – Brussels IVF
-
Sep 4, 2026, 16:48Vikrant Bhatia: In Fertility Care, More Information Doesn’t Always Mean Better Decisions
-
Sep 4, 2026, 16:46Priyadatt Patel: Few Numbers Cause as Much Unnecessary Distress as AMH
-
Sep 4, 2026, 16:43Amos Grünebaum: Ask a Pregnant Woman What Her Chance of a Cesarean Is, Then Ask Her Obstetrician
