In some circumstances, a man’s ejaculate may contain very few healthy sperm or even no healthy sperm at all. This is referred to as azoospermia or oligospermia/cryptozoospermia. Reasons for this include:
An inoperable blockage, lack of or severing of the vas deferens
An extremely reduced sperm production or no sperm production at all – for example, caused by genetic defects, environmental toxins, infections, an undescended testicle during childhood that was treated too late or by varicose veins of the testes
Furthermore, it may be the case that a man cannot ejaculate, due to a tumour or paraplegia for example. In such cases, pregnancy by natural means is usually not possible.
In cases like these, however, there are often still sperm capable of fertilisation in the man’s epididymides or testes. A doctor can retrieve these during a minor surgical procedure. To do this, testicular sperm extraction (TESE) can be used.
