Module 8: Figure intracytoplasmic sperm injection

Artificial insemination by intracytoplasmic spermatozoa injection (ICSI) of a human oocyte.

A. A blunt electrode on the left holds the oocyte in place ready to be penetrated by a sharp microinjection needle containing a single spermatozoon (arrow). B. The needle is pushed against the oocyte and causes it to dimple before it penetrates. C. The spermatozoon is injected into the cytoplasm of the oocyte. D and E. The needle is withdrawn, leaving the spermatozoon in the cytoplasm. F. At 2 min after injection, the intact spermatozoon is clearly visible within the cytoplasm of the oocyte. Reproduced from Tesarik, J. and Mendoza, C. (1999) In vitro fertilization by intracytoplasmic sperm injection. BioEssays 21:791–801, with permission from John Wiley and Sons, Inc.; Copyright 1999 Wiley-Liss, Inc., A Wiley Company; see Tesarik and Mendoza 1999.