Probability to retrieve testicular spermatozoa in azoospermic patients

The degree of probability to retrieve spermatozoa from testicular tissue for intracytoplasmic sperm injection into oocytes is of interest for counselling of infertility patients. We investigated the relation of sperm retrieval to clinical data and histological pattern in testicular biopsies from azoospermic patients.

In 264 testicular biopsies from 142 azoospermic patients, the testicular tissue was shredded to separate the spermatozoa, histological semi-thin sections of which were then evaluated using Johnsen score.

The retrieval of spermatozoa correlated significantly ( P < 0.001) with the testicular volume ( r = 0.49), the FSH concentration ( r = -0.66), the maximum score (r = 0.85) and the mean Johnsen score (r = 0.81). In the multivariate regression analysis the successful testicular sperm extraction showed the closest relationship to the maximum score. The testicular volume correlated significantly with the mean Johnsen score ( r = 0. 64, P < 0. 001), and the basal serum FSH concentration mainly with the maximum score ( r = - 0.77; P < 0.001). Patients with a history cryptorchidism showed a significantly lower Johnsen score compared to the patients who did not have any testicular disease in the past (3.7 +/- 2.4 vs. 5.9 +/- 2.5; P < 0. 01).

In a limited range, the testicular volume and the FSH concentration in serum were related to the Johnsen score which correlated significantly with the sperm retrieval. The successful sperm retrieval can be expected in all azoospermic patients irrespective of the results of clinical examination. However, the probability of retrieval of spermatozoa decreased significantly in patients with a FSH level > 18 U/L, testicular volume < 5 mL, mean Johnsen score <5, and maximum Johnsen score <7.