Polar body biopsy The oocyte is then inseminated using the intracytoplasmic sperm injection (ICSI) technique and is kept in culture in an incubator. In order to biopsy the polar body, the oocyte is held by the holding pipette with the polar body at the 11-12 o'clock position. An opening is made in the zona pellucida and a polished glass needle is introduced into the perivitelline space and the polar body is carefully removed.