Michal Shelef

Morphology and clinical outcomes of embryos after in vitro fertilization are superior to those after intracytoplasmic sperm injection

OBJECTIVE To compare embryos obtained after IVF and intracytoplasmic sperm injection (ICSI) regarding morphology and the likelihood of achieving clinical pregnancy. DESIGN Case-control study. SETTING An IVF unit controlling 1,310 cycles in 1996. PATIENT(S) Women having a total of 477 IVF and 475 ICSI consecutive cycles. INTERVENTION(S) Ovarian stimulation, IVF-ET, or ICSI-ET for all couples. MAIN OUTCOME MEASURE(S) Number of grade-A embryos transferred, preclinical pregnancy losses, and clinical pregnancy rates in IVF and ICSI cycles. RESULT(S) In comparison with the ICSI group, the IVF group showed significantly more grade-A embryos available for transfer (mean, 2 +/- 1.6 versus 1.8 +/- 1.5), significantly fewer preclinical pregnancy losses (1.6% versus 4%), and significantly higher clinical pregnancy rates (25% versus 19.1%). CONCLUSION(S) Embryos obtained after IVF are superior to those obtained after ICSI in relation to embryo morphology and the likelihood of achieving clinical pregnancy.

Fibrin glue improves pregnancy rates in women of advanced reproductive age and in patients in whom in vitro fertilization attempts repeatedly fail

OBJECTIVE To evaluate the possible contribution of fibrin sealant to the ET stage of IVF. DESIGN Case-control study. SETTING An assisted reproductive technology unit that performed 2,535 treatment cycles from 1996-1997. PATIENT(S) All consecutively seen patients who underwent ET from January 1996 to September 1997. INTERVENTION(S) All women who underwent ET with the aid of fibrin sealant during the study period were compared with those who underwent standard ET (controls). Thereafter, a case-control study was conducted on the first consecutively seen 174 women who underwent ET with fibrin sealant and a control group that was matched for age and number of previous unsuccessful cycles. MAIN OUTCOME MEASURE(S) Patient age, number of previous unsuccessful IVF attempts, number of embryos transferred, and pregnancy rates. RESULT(S) During the study period, ET was performed with fibrin sealant in 265 women and by the standard procedure in 1,402 women. Women in the fibrin sealant group were significantly older. The pregnancy rate was not significantly different between the groups in the whole-cohort study (20.4% versus 23.1%), but it was significantly higher in the fibrin sealant group in the case-control study (25.3% versus 14.9%). This also was true when the older women (>35 years) and the women with > or =4 previous failed IVF attempts were analyzed separately (23.2% versus 9.8% and 26.1% versus 13.4%, respectively). CONCLUSION(S) The use of fibrin sealant in ET appears to be beneficial in women of advanced reproductive age and in patients in whom IVF attempts repeatedly fail.

The prognostic value and significance of preclinical abortions in in vitro fertilization-embryo transfer programs

UNLABELLED Preclinical abortions occur in natural conceptions as well as in in vitro fertilization-embryo transfer (IVF-ET) cycles. Nevertheless, although known, this entity is ill defined. OBJECTIVE The purpose of this study was to propose a classification of these pregnancies on the basis of pathophysiological evidence and to evaluate their future clinical impact. DESIGN Of 970 IVF-ET cycles, 114 cycles (11.7%) terminated in preclinical abortions. Abortions were divided according to peak beta human chorionic gonadotropin (beta-hCG) values into chemical abortions (52%) occurring 2 weeks after ET with beta-hCG values not higher than 21 mIU/mL and peri-implantation abortions (47%) terminating spontaneously 4 weeks after ET; the latter had higher beta-hCG values for a longer period of time but without any sonographic evidence of gestational sac. No woman in the two groups needed curettage. RESULTS After a chemical abortion, the pregnancy outcome had better ongoing pregnancy rates (24.7%) in comparison with the 17% achieved in the total IVF-ET cycles. CONCLUSIONS It is concluded that these two groups most probably have different pathophysiological backgrounds and concomitantly different future clinical impacts.

Comparison of embryo quality between intracytoplasmic sperm injection and in vitro fertilization in sibling oocytes

BackgroundThe aim of the present study was to compare the quality of embryos derived from sibling oocytes by in vitro fertilization (IVF) or ICSI.MethodsConsecutive patients with a less than 40% fertilization rate in a previous standard IVF cycle or with relative male factor infertility were recruited for the study. The oocytes retrieved from each patient were divided into two groups for either conventional insemination (group A) or ICSI (group B). Power analysis showed that to detect a 25% difference in the rate of high-quality embryos between the groups with a power of 0.8, at least 1,200 oocytes were needed in each group.ResultsOne hundred seventy-seven patients were included in the study. Group A was comprised of 1,526 oocytes and group B of 1,480 sibling oocytes. As expected, the fertilization rate was significantly higher in group B than group A (67.1 vs. 43.6%, p < 0.001). No significant between-group differences were observed in cleavage rate (92.7 and 89.7%, respectively) and the rate of either grade A embryos (22.6 and 23.9%, respectively) or grade A1 embryos (37.3 and 33.5%, respectively).However, in the subgroup of patients with relative male-factor infertility (n = 36), the rate of grade A1 embryos was significantly higher in the IVF than the ICSI group (46.4 vs. 29.0%, respectively, p = 0.02).ConclusionsEmbryo quality does not seem to be influenced by the mode of fertilization (IVF or ICSI). We assume that embryo quality depends on intrinsic factors of the gametes involved rather than on the fertilization process per se.

Reinsemination in human IVF with fresh versus initial semen: a comparative study.

In the event of non-fertilization of oocytes at the first insemination, repeat insemination is often successful in the IVF procedure. Nevertheless, the value of reinsemination is still controversial. In 56 out of 132 (42%) women treated in our IVF-ET Unit for mechanical infertility by identical induction and aspiration protocols, reinsemination of one or more ova was required. They were divided into two groups. Group I: 79 oocytes from 32 women who were reinseminated with initial semen 24 hours following primary insemination. Group II: 57 oocytes from 24 patients who were reinseminated with fresh semen 24 hours following primary insemination. Fertilization, cleavage and pregnancy rates differed significantly in group I as compared to group II (21.2%, 37.3%, p less than 0.005; 18.6%, 31.9%, p less than 0.001; 18.4%, 29.1%, p less than 0.001). We conclude that reinsemination is a beneficial procedure in cases of non-fertilization of oocytes at the first insemination. Furthermore, the use of fresh semen is preferred to achieve higher fertilization, cleavage and pregnancy rates.

The impact of the refractory period to gonadotropin therapy in IVF-ET cycles post longacting gonadotropin-releasing hormone (GNRH) analogue

Sixty-nine women were treated with a long-acting gonadotropin-releasing hormone analogue (GnRHa), D-Trp-6-LH-RH (DTRP6) 3.2 mg (Decapeptyl, Ferring, Kiel, F.R.G.) prior to induction of ovulation for in vitro fertilization (IVF) with human menopausal gonadotropin (hMG; Pergonal; Serono Laboratories, Inc., Randolph MA). Three types of response were noted: Group I (18 patients) responded between days 1-3 of the treatment; Group II (30 patients) responded between days 4-6 of the therapy, and Group III (21 patients) responded after 7 days of treatment. Although a higher number of oocytes were encountered in Group I than in the latter two groups fertilization and clinical pregnancy rates were lower than in Group II (P less than 0.05), respectively, but higher than in Group III (P less than 0.07 and P less than 0.01), respectively. The best results were achieved by Group II patients, while Group III seemed to represent low responders as the number of embryos and pregnancy rate were significantly lower than in the other two groups. It seems that the level of ovarian suppression achieved by GnRH analogue results in a period of refraction of the ovary, and its duration has most probably an effect upon the results of the IVF cycles.

GnRH agonist increases pregnancy potential of retrieved oocytes given adequate preincubation before insemination: a comparative study

Preincubation of oocytes aspirated from follicles in IVF-ET programs is a controversial approach. While some investigators recommend this technique others doubt its necessity. We have studied the embryo quality in 100 women, undergoing IVF-ET, in whom ovulation was induced by the combination of GnRH agonists (GnRHa) and menotropins and compared to a control group in whom ovulation was induced with menotropins alone. No statistically significant difference was noted with regard to the fertilization and cleavage rates as well as to the preincubation period. Significantly higher pregnancy rates (P less than 0.001) were encountered in the first group in comparison with the control group.