D. Mitchell-Leef

Comparison of ICSI and conventional IVF in patients with increased oocyte immaturity

Using sibling oocytes, the objective of this study was to compare the intracytoplasmic sperm injection (ICSI) fertilization rates to those achieved with conventional IVF in patients with high rates of oocyte immaturity. This study was observational in nature, and included 91 patients who were treated using split insemination techniques. The fertilization rates for the ICSI group and the IVF group were 41.1 +/- 15.0% and 53.2 +/- 19.8%, respectively (P <: 0.0001). There was no significant difference in day-3 embryo quality between the two groups. There was a significantly higher number of embryos frozen in the IVF group than in the ICSI group: 357 (84.8%) and 297 (76.7%), respectively (P = 0.037). Furthermore, the number of embryos either transferred or frozen was significantly higher in the IVF group than the ICSI group: 459 of 1173 (39.1%) and 385 of 1268 (30.4%), respectively (P < 0.0001). These data indicate that conventional IVF results in a higher fertilization rate than ICSI. Furthermore, IVF provided more embryos available for transfer or cryopreservation when compared with ICSI, thereby optimizing the patients cycle.

Poor implantation of cryopreserved reinsemination-fertilized human embryos

OBJECTIVE To investigate whether a poor rate of implantation after in vitro fertilization (IVF) was due to poor embryonic/endometrial synchrony during the original IVF cycle, we have cryopreserved reinseminated-fertilized embryos for later more synchronous replacement after thawing. The chance of implantation of fresh reinseminated fertilized human oocytes is approximately one tenth that of timely fertilized embryos. STUDY DESIGN AND DATA: Retrospective study of 35 original oocyte collections in which initial normal fertilization was 47.3% (129/273 oocytes), with 49.6% fertilization (67/135) upon reinsemination. Of these, 70 initially fertilized and 67 reinsemination-fertilized embryos were cryopreserved, and 50 initially fertilized and all 67 reinsemination-fertilized embryos were subsequently thawed with 72% and 63% cryosurvival, respectively, (not significant). SETTING Private infertility clinic. RESULTS In 11 cycles, 23 thawed initially fertilized embryos (group A) were replaced with a 21.7% implantation rate per embryo; in 10 cycles, 13 initially fertilized and 12 reinsemination-fertilized embryos (group B) were replaced together with an 8% implantation rate; finally, in 16 cycles, 30 reinsemination-fertilized embryos (group C) were replaced with a 3.3% implantation rate (group A versus group C: P = 0.076). Comparison of clinical pregnancies between these groups was significantly different (6/11 versus 1/16; P = 0.0427). CONCLUSION Reinsemination-fertilized embryos survive freezing as well as initially fertilized embryos, but better embryonic/endometrial synchrony does not improve chances of their implantation.

The significance of platelet-activating factor and fertility in the male primate: a review

Abstract:  Since its discovery nearly 30 years ago platelet‐activating factor (PAF) has emerged as one of the more important lipid mediators known. PAF (1‐O‐alkyl‐2‐O‐acetyl‐sn‐glycero‐3‐phosphorylcholine) exists endogenously as a mixture of molecular species with structural variants of the alkyl moiety. PAF is a novel potent signaling phospholipid that has unique pleiotropic biological properties in addition to platelet activation. PAF also plays a significant role in reproduction and is present in the sperm of a number of primate species. PAF content in squirrel monkey sperm is significantly higher during the breeding season than the non‐breeding season. PAF content in rhesus sperm has a significant relationship with sperm motility. PAF content in human sperm has a positive correlation with seminal parameters and pregnancy outcomes. The enzymes (lyso‐PAF‐acetyltransferase and PAF‐acetylhydrolase) necessary for PAF activation and deactivation are present in primate sperm. PAF‐acetylhydrolase may act as a ‘decapacitation factor’. Removal of this enzyme during capacitation promotes PAF synthesis increasing primate motility and fertilization. PAF also plays a significant role in the fertilization process, enhancing the fertilization rates of oocytes. Enhanced embryo development has also been reported in oocytes fertilized with PAF‐treated sperm. Exogenous PAF will also significantly improve primate artificial insemination pregnancy outcomes. PAF antagonists inhibit sperm motility, acrosome reaction, and fertilization thus suggesting the presence of receptors for PAF. The PAF‐receptor is present on primate sperm, with altered transcript levels and distribution patterns on abnormal cells. Whereas, the exact mechanism of PAF in sperm function and reproduction is uncertain, its importance in normal primate fertility is substantial.

Exposure of preimplantation embryos to platelet-activating factor increases birth rate.

AbstractProblem: Platelet-activating factor (PAF) plays a significant role in fertility. Preimplantation stage embryos produce PAF (ePAF) which is required for development. PAFs mechanism of action is receptor-mediated and its presence has been reported in the developing mouse and human embryo. Exposure of preimplantation stage mouse embryos results in higher implantation rates. However, the effect of such treatment on live-birth rates and birth weights has not been reported. Therefore, the objective the study was to determine the effect of exposing preimplantation mouse embryos to PAF on subsequent birth rate and weight. Design: Two-cell stage preimplantation stage mouse embryos exposed to PAF (10−7 M) for 15 min prior to intraoviductal transfer. Methods: Preimplantation stage embryos were recovered from eCG/hCG primed BDF1 female mice. Embryos were exposed to synthetic PAF (10−7 M) for 15 min. PAF-treated embryos were transferred to the oviducts of pseudopregnant female CD-1 female mice. Superovulated and cultured BDF1 embryos not treated with PAF served as in vitro controls and naturally ovulated embryos with no collection/culture served as in vivo controls. Embryos were permitted to develop to term (18–21 days). The number of pups born per litter and litter weights subsequently were recorded. Results: A total of 160 BDF1 mouse embryos were collected, treated, and transferred (20 per CD-1 recipient) as described. There was a significant (P<0.05) increase in the number of pups born to the PAF treatment group (56/80; 70%) as compared to the control group (44/80; 55%). There was also a significant difference (P<0.05) in litter birth weights between the PAF (1.31 g/litter) and controls groups (1.25 g/litter). There was a significant difference (P<0.05) in birth weights between the PAF treatment group and the in vivo group (1.51 g/litter). There was a significant difference in birth weights between the in vitro control and in vivo groups (1.51 g/litter). There were no observational malformaties to pups born in any group. Conclusions: Brief exposure of preimplantation stage embryos to PAF will result in a significant increase of delivery rates (pups/litter) as well as birth weights. However, the increase of birth weight was significantly below that found naturally. Additional studies are warranted to elucidate the mechanism of PAFs action in the preimplantation stage embryo and subsequent uterine development.

Fertilization Potential of Human Sperm Is Correlated with Endogenous Platelet-Activating Factor Content

AbstractPurpose: Platelet-activating factor (PAF) is a potent signaling phospholipid that is found in mammalian sperm and has a positive correlation with fertility. Whereas PAF is present in human sperm, there are no relational reports on its content and the cells fertilization potential. Therefore, the study objective was to determine if PAF content in capacitated-induced sperm is related to fertilization potential as determined by the sperm penetration assay (SPA). Methods: Endogenous sperm lipids were measured for PAF content by a specific radioimmunoassay following insemination of zona pellucida-free hamster ova. Data were analyzed by regression analysis and Students t test. Results: Regression analysis revealed a positive and significant relation (R2 = 0.806; P < 0.05) between PAF content in human sperm and SPA outcome (pass: ≥5.0; fail: <5.0, penetrations/ova). Patients that passed (22.61 ± 5.21 picomoles/106) the SPA had significantly (P < 0.01) higher PAF levels in their sperm than patients that failed (12.91 ± 1.76 picomoles/106 cells) the test. Conclusions: PAF content in capacitated-induced sperm has a significant and positive relationship with fertilization potential. Fertilization potential may be predicted by measuring PAF levels in capacitation-induced human sperm. Determining PAF content in capacitated human sperm may be a beneficial diagnostic tool for the infertility specialist.

Minimal stimulation with simplified monitoring for in vitro fertilization

PurposeThis 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.ResultsDuring January 1992 through December 1993, 165 stimulation cycles resulted in 137 egg retrievals, 24 clinical pregnancies (17.5%), and 20 viable pregnancies (14.5%). Cycles that could not be completed (28/165 or 16.9% of all cycles) involved luteinizing hormone surges, insufficient follicles, or low estradiol levels. There were no pregnancies in patients who were 40 years or older or who received 200 mg daily doses of clomiphene citrate. The viable pregnancy rate among patients with male factor infertility was 7.7% (2/26). For non-male-factor infertility patients who were younger than 40, the viable pregnancy rate was 17.6% (18/102).ConclusionThe simplified monitoring method did not appear to compromise the results.

Evaluation of the first one hundred and thirty one live births following oocyte cryopreservation from a single ivf program utilizing a standardized vitrification technique

OBJECTIVE: Oocyte cryopreservation by vitrification is an efficient procedure, however, limited data is available addressing the safety of this technology. For this reason we analysed live birth outcomes obtained after egg freezing in a comparable patient population. DESIGN: Retrospective, matched control study. MATERIALS AND METHODS: From December 2006 to December 2009, live birth outcomes from 90 deliveries following vitrified donation cycles & from 112 fresh egg donation cycles were tabulated and analysed. Cryopreservation of oocytes was performed by minimum volume vitrification. Oocytes were fertilized by 40 hrs after HCG adminisration (fresh egg donation) or 2-3 hrs after oocyte warming (cryo egg donation) Results were analysed by the One-way Anova or the Fisher’s exact tests, as appropriate (P<0.05). RESULTS: Parameters of live birth outcomes are reported in Table 1.