Infertility is the failure to conceive after regular unprotected sexual intercourse for at least 1 year. Male factor infertility is responsible for an estimated 25% of all cases of couple infertility. Azoospermia is found in approximately 15–20% of infertile men. The causes of azoospermia can be divided into obstructive and non-obstructive. Obstructive azoospermia (OA) may be due to an obstruction at any point along the male reproductive tract. It is usually associated with normal sized testis and hormonal profile, with dilatation of the epididymis. A past history of a vasectomy, inguinal hernia repair or symptoms of haematospermia with ejaculatory pain all suggest a possible cause of obstructive azoospermia.

Non-obstructive azoospermia (NOA) is usually due to failure of spermatogenesis. Clinically, these men may have a small testis with an elevated Follicular Stimulating Hormone (FSH) . However NOA may exist in men with normal sized testes and normal FSH levels in men with late spermatogenic arrest. A past history of crytoorchism, chemotherapy especially at a young age or infections affecting the genital (i.e. Mumps orchitis) may all be elicited in the history.

In this chapter we will be discussing our recommended methods of sperm retrieval in this population.

A detailed history and examination is vitally important. The history should be used to determine both normal function of the reproductive tract (erectile and ejaculatory function) and pathological or congenital processes which may have adversely affected fertility. Examination is to determine normal secondary sexual characteristics, presence of surgical scars in the groin or scrotum and the size of the epididymis, vas and testis. A testis length of less than 4 cm may be associated with testicular failure and non-obstructive azoospermia. However, it is important to note that racial differences in genitalia size exist. The absence of the vas either unilaterally or bilaterally may be associated with a genetic abnormality of the cystic fibrosis gene; it is usually associated with obstructive azoospermia. Dilatation of the epididmyi suggests an obstructive element which may be amenable to reconstruction.

Table 15.1 illustrates the required investigations for these patients . These investigations aid in determining whether the patient has obstructive or non-obstructive azoospermia as well as identifying other conditions which may affect fertility.

Two semen analyses are usually required to confirm azoospermia. The presence of low volume, absent fructose and an acid PH are pathognomonic of ejaculatory duct obstruction (EDO) or seminal vesicle atresia. Both of these conditions are causes of obstructive azoospermia. Seminal atresia occurs in congenital bilateral absence of the vasa (CBAVD). EDO may be due to a congenital Mullerian duct cyst or stenosis of the ejaculatory ducts.