intracytoplasmic sperm injection (ICSI) to achieve a pregnancy. ICSI is an IVF procedure that involves injecting a single sperm directly into an egg. ICSI is different from conventional in vitro fertilization (IVF), where sperm placed in a dish with an egg can penetrate and fertilize it on its own. ICSI may be helpful in cases of severe male-factor infertility, such as cryptozoospermia, where there are very few sperm in the semen.
If sperm is difficult to find in the ejaculated semen, it may need to be extracted directly from the testicles in a process known as TESE (testicular sperm extraction) or TESA (testicular sperm aspiration). This can be helpful in cases where sperm is damaged as it moves through the reproductive tract Age may make a difference; they indicates that ejaculated sperm achieves a higher birth rate for men under 35, while testicular may be a better option for older men.