In two separate prospectively randomized trials, intracytoplasmic sperm injection (ICSI) cycles were studied in a controlled manner to monitor the effects of either bovine oviductal epithelial cell co-culture (n = 119) or assisted hatching by zona drilling (n = 100). In the first study, immediately following ICSI, all eggs were placed directly either onto partial monolayers of bovine oviductal cells or into regular culture medium. Although the embryo developmental rate was apparently compromised in part by the presence of the co-culture cells, ultimately there were no significant differences in either the viable pregnancy rate (31.6% co-culture versus 29.0% control) or the embryonic implantation rate (11.4% co-culture versus 13.6% control). Assisted hatching also had no significant impact on ICSI cycle outcome in terms of either the viable pregnancy rate (30.0% assisted hatching versus 32.0% control) or the embryonic implantation rate (8.5% assisted hatching versus 13.5% control). However, in female patients aged > or = 35 years, assisted hatching appeared to convey a marginally significant benefit in terms of both the viable pregnancy rate (35.5% assisted hatching versus 11.1% control) and the embryonic implantation rate (10.3% assisted hatching versus 3.1% control). It seems that the overall improvement of ICSI cycle outcome cannot be achieved by the general application of either co-culture or assisted hatching. Nevertheless, it is possible that there remain specific patient groups that might benefit from selected use of either of these modalities.

The consequences of sperm choice for fertilization have never been more relevant than since the advent of intracytoplasmic sperm injection (ICSI) in assisted human reproduction, Prior to ICSI there had always been an element of 'natural' sperm selection in the making of an in-vitro embryo, This de-emphasis on the need for spermatozoa of a certain quality, at least in postnatal terms, has not led to an apparent increase in abnormal offspring. Much precedes the delivery of a child, however, and to some extent long-term developmental follow-up of offspring is also necessary to confirm the present ease of acceptance of ICSI, The possibility that a spermatozoon and its quality might have an impact beyond that of being the simple initiator of early embryonic development has intrigued some investigators, They have suggested how such additional factors of sperm influence may be perceived in tel ms of conventional fertilization in IVF with subsequent development to blastocyst, or to term pregnancy. Removal of a major hurdle, fertilization failure, to embryonic development and pregnancy through the use of ICSI may allow us to focus more specifically on the impact of the quality of a single spermatozoon on embryogenesis, and in so doing might provide more accurate analysis of the concerns that apply to the routine use of ICSI.

This retrospective analysis was designed to assess the performance of human embryos following cryopreservation based on whether they were originally developed in standard culture medium (65 cycles, 223 embryos) or cocultured on partial monolayers of bovine oviductal epithelial cells (63 cycles, 198 embryos). Embryo cryosurvival and implantation were compared between the study group and the contemporaneously matched controls.

Objective: To analyze the introduction of a new assisted fertilization technique for the treatment of severe male factor and idiopathic fertilization failure infertilities.Design: Retrospective analysis of 16-month clinical application of IVF-ET where insemination was performed solely by direct intracytoplasmic sperm injection.Setting: Clinical IVF-ET program.Patients: Ninety-two couples undergoing 105 cycles of sperm injection.Results: One hundred embryo transfers yielded 28 viable pregnancies (28%) from which eight normal deliveries have occurred to date. Complete cleavage arrest or fertilization failure occurred in four cycles, and one couple had all embryos cryopreserved. One thousand one hundred forty-three eggs were injected of which 173 (15%) degenerated. Four hundred seventy-nine of the surviving 970 eggs became normally fertilized (49%), and 381 of these zygotes (79.5%) developed suitably for cryopreservation or for transfer. Thirty-four of 310 embryos transferred implanted, yielding an implantation rate of 11%. Both testicular and epididymal sperm were used successfully to achieve fertilization and pregnancies, as was sperm retrieved by electroejaculation. Older women and couples suffering from prior idiopathic fertilization failure had a markedly poorer outcome.Conclusions: These results confirm that the intracytoplasmic sperm injection technique is a successful form of assisted fertilization that can be applied to a wide range of couples at significant risk from fertilization failure.

In this study, 141 couples underwent 163 cycles of in vitro fertilization (IVF) and embryo transfer in which the eggs were inseminated by intracytoplasmic sperm injection (ICSI). Overall, 41% of the injected eggs were normally fertilized and 81% of the resulting embryos were suitable for cryopreservation (91 embryos) or uterine transfer. From 153 fresh embryo transfers, 45 ongoing or delivered pregnancies (27.6% per cycle) were achieved, and of the 507 embryos transferred, 54 successfully implanted giving an implantation rate per embryo of 10.7%. Five additional pregnancies did not yield a viable fetus or underwent a spontaneous abortion, giving a miscarriage rate of 10% (5/50). Increased maternal age or a prior diagnosis of failed fertilization after conventional IVF had a significantly negative impact on success. Sperm from the testis and epididymis, those retrieved by electro-ejaculation, and completely immotile ejaculated sperm all gave rise to pregnancies. ICSI reinsemination was used with limited success to rescue failed fertilization cycles, although the implantation rate per embryo was poor (5%). ICSI has greatly improved the ability to use IVF for treating couples with a poor fertilization potential.

This retrospective, descriptive study was designed to determine the effectiveness of using clomiphene citrate in relatively high daily doses (100, 150, and 200 mg) with simplified monitoring for in vitro fertilization in a private office and surgical center. The self-selected study population comprised 109 women who were 25–42 years old, including 26 women whose husbands had mild male-factor infertility.

Older patients and those who consistently return for embryo transfer but without implantation were studied to see if a combination of day 3 assisted hatching and co-culture (AH+CC) might be beneficial compared to assisted hatching alone (AH-alone). Female patients of > or = 38 years and couples who had previously failed to implant embryos three times or more were prospectively and randomly assigned to either an experimental or a control group. In the experimental group all embryos were co-cultured on partial monolayers of bovine oviductal epithelial cells for 2 days followed by assisted hatching by zona drilling (AH+CC). All control embryos were cultured by standard procedures until day 3 when they also underwent zona drilling prior to uterine transfer (AH-alone). With 50 cycles in each group there was unfortunately a marginal bias against the AH+CC group in that these patients had undergone a higher number of previous transfer cycles. There was a marginally lower percentage of fragmentation and a significantly higher degree of zona thickness variability in the AH+CC embryo group. Embryonic implantation was significantly increased (P < 0.05) in the AH+CC group (18%) when compared to the AH-alone group (10%). This difference was reflected in a significantly higher (P < 0.05) initial pregnancy rate (52 versus 32%) in the AH+CC group, and a higher (not significant) viable pregnancy rate (38 versus 22%).