During in vitro egg retrieval the size and number of follicles are recorded for each follicle punctured by the puncture needle to retrieve eggs, and the aspirated follicular fluid is examined microscopically to see if there are any eggs.
In vitro egg retrieval is performed under ultrasound monitoring, and the doctor retrieving the eggs will generally measure the size of each follicle and record it before puncturing the follicle into the ovary for aspiration. Each follicle punctured is documented and these records can be found in the medical record of the egg retrieval procedure.
After each follicle is punctured follicular fluid is aspirated using negative pressure and the aspirated follicular fluid is sent to the laboratory. The laboratory places the aspirated follicular fluid under a microscope, looks for eggs in the follicular fluid, removes them for fertilization, and records the number of eggs obtained.