Human Reproduction vol.10 no.5 pp.1152-1155, 1995 Pregnancies after microsurgical correction of partial epididymal and vasal obstruction R.Hauser 1 - 2 ' 3 , P.D.Temple-Smith 2 , GJ.Southwick 2 , J.McFarlane 1 and D.M.de Kretser 1 'institute of Reproduction and Development and 2 Male Infertility Microsurgery Research Programme, Department of Anatomy, Monash University, Clayton, Victoria 3168, Australia 3 To whom correspondence should be addressed at: 16 Alumim Street, Tel Aviv 69690, Israel A group of 16 infertile patients suspected of having a partial epididymal obstruction on the basis of severe oligo- zoospermia, normal-sized testes and a normal serum follicle-stimulating hormone, underwent scrotal explora- tion. Evidence of partial obstruction of the epididymis was found in 13 cases and of the vas deferens in one case, and was supported by finding normal spermatogenesis on testicular biopsy. Vasoepididymostomy or vasovasostomy were performed, resulting in a significant improvement of semen analysis in 50% of cases and in six pregnancies in two patients. The diagnosis of partial epididymal obstruction should be considered when the above criteria are met. If pregnancies do not result when intracytoplasmic sperm injection (ICSI) is used with the ejaculated spermatozoa, a testicular biopsy followed by a microsurgical by-pass procedure should be considered whenever normal spermatogenesis is diagnosed. In all cases, the epididymal spermatozoa should be aspirated during the operation and either used immediately for insemination or stored frozen. The remarkable results of the new artificial repro- duction technologies and in particular ICSI, question the indication for microsurgical correction in cases of partial epididymal obstruction. Key words: epididymis/infertility/microsurgery/oligozoospermia/ vasoepididymostomy Introduction Extremely severe oligozoospermia (<1X1O 6 total sperm count/ml) is a well recognized cause of male infertility and has a poor prognosis. It has been suggested that partial obstruction of the epididymis is a cause of this state in some patients; previous studies claimed that 10-25% of all severe oligozoospermic patients had a partial obstruction (Silber and Rodriguez-Rigau, 1981; Schoysman, 1988). The presence of severe oligozoospermia accompanied by vigorous spermato- genesis, as revealed by a testicular biopsy, was considered as an indication of a partial obstruction to sperm outflow, which 1152 might be reversed by microsurgical procedures (Silber and Rodriguez-Rigau, 1981; Schoysman, 1988). We report on a series of 16 infertile patients with extremely severe oligozoospermia in whom testicular biopsies showed spermatogenesis ranging from normal to severe hypospermato- genesis and who underwent testicular exploration and micro- surgical by-pass procedures. The indications for such procedures in the face of the new assisted reproductive technologies currently available are discussed in the light of these results. Materials and methods Patients The outcome of 16 male patients aged 25—48 years (mean 32.0 ± 5.8 SD) with extremely severe oligozoospermia and infertility, who were referred to the andrology microsurgical clinic for investigation, was retrospectively analysed. Of this group, 15 had primary infertility lasting 1-10 years and one had secondary infertility of 11 years duration with a documented episode of epididymitis 5 years earlier. Five patients had attempted in-vitro fertilization (IVF) procedures in the past but the rest had been rejected for IVF due to poor semen characteristics. All men had a physical examination with special emphasis on male secondary sexual characteristics, testicular volume and possible congenital absence of parts of the sperm transport system. Eight of the patients reported symptoms or findings suggestive of the incidence of genital infections in the past (epididymitis, urethritis, etc.). Semen analyses and antisperm antibody assessment Several semen analyses over a period of up to 10 years were obtained in each patient and were repeated before the operation to validate the diagnosis. Antisperm antibody assessment in serum and seminal plasma were performed in all patients using an indirect immunobead test (IIBT) for immunoglobulin (Ig) G and IgA (Bio-Rad Laboratories, Richmond, CA, USA). Positive results were considered when 50% of the spermatozoa bound immuno- beads, for both serum and seminal plasma tests. Hormone assays Serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were measured in all patients by specific radio- immunoassays employing the World Health Organization inter- national reference standards (69/104 and 78/549). The normal range for FSH in males was 0.9-7.0 mlU/ml and the normal range for LH was 0.9-13.0 mlU/ml. Serum © Oxford University Press