How does the angle of micropipette insertion affect oocyte viability ?

• Shallow Angles (25–35°) minimize shear forces on the oolemma and reduce the risk of scraping against the dish.

• Steeper Angles (>45°) can cause the pipette tip to “dig in,” increasing membrane tears and cytoplasmic leakage.

• Optimal: Aim for ~30° so the pipette penetrates the zona and oolemma smoothly, preserving spindle integrity.