Receiving spermatozoa by operative methods (TESE I MESA)
Even if the spermatozoa are completely absent in the ejaculate, they can be obtained directly from the testicles by TESE (testicular sperm extraction) or epididymides by the MESA method (microsurgical epididymal aspiration of sperm). During this small surgical operation, a doctor can obtain a microscopic piece of tissue containing spermatozoa.
The obtained spermatozoa have a laboratory preparation for fertilization by ICSI. After fertilization, the embryos are cultured and transferred to the uterine cavity, as in the IVF procedure.
It should be borne in mind that in the case of severe non-obstructive oligozoospermia, as well as azoospermia of obstructive and non-obstructive origin, infertility may have genetic causes.