Artificial Insemination Artificial insemination has been used mainly to treat unexplained infertility (usually combined with superovulation) and male factor infertility (including same sex female couples). All artificial insemination procedures involve the placement of whole semen or processed sperm into the female reproductive tract, which permits sperm–ovum interaction in the absence of intercourse. The placement of whole semen into the vagina as a mode of fertility treatment is now rarely performed except in cases of severe coital dysfunction. Currently, all of the common forms of artificial insemination involve processed sperm obtained from the male partner or a donor. Many techniques for artificial insemination have been described, but only intracervical and intrauterine inseminations (IUI) have been routinely employed. The success rates with intracervical insemination are lower than those with IUI, particularly when using frozen sperm (66–68).
Insemination Processing During and after intercourse, seminal ﬂuid usually is prevented from reaching the intrauterine cavity and intra-abdominal space by the cervical barrier. The introduction of seminal ﬂuid past this barrier may be associated with pelvic infection and severe uterine cramping or anaphylactoid reactions, possibly mediated by seminal factors such as prostaglandins. Thus, protocols for processing whole semen include the washing of specimens to remove seminal factors and to isolate pure sperm. Additional processing may include centrifugation through density gradients, sperm migration protocols, and differential adherence procedures (66). Finally, phosphodiesterase inhibitors, such as pentoxiphylline, have been used during semen processing in an attempt to enhance sperm motility, fertilization capacity, and acrosome reactivity for IVF procedures (60,69).
Azoospermia: Classification and Treatment
Intrauterine Insemination IUI is the best studied and most widely practiced of all the insemination techniques. It involves placement of about 0.3 to 0.5 mL of washed, processed, and concentrated sperm into the intrauterine cavity by transcervical catheterization (66). Patients should remain immobile for approximately 15 minutes following the procedure (70). Studies of the efficacy of IUI in the treatment of male factor infertility have been difficult to assess because of variations in inclusion criteria and the limitations of sperm function tests. Although it makes intuitive sense that IUI would result in higher pregnancy rates rather than timed intercourse in the case of male factor subfertility, there are conﬂicting reports of the benefits of IUI (66,71–74). Ideally, the total motile sperm count in the IUI specimen should be 5 million or 10 million or more (75–78). Pregnancy rates with semen meeting those thresholds have been reported to be 10.5% per cycle and 38% after 4 to 6 cycles (77,78). No benefit has been found with respect to double IUI versus single IUI during a single cycle (79).