Semen evaluation following preparation for in vitro fertilization of human oocytes

Significance of chromosomal aberrations for the unsuccessful procedures of assisted reproduction

Lymphocyte cultures from patients who had previously undergone at least three unsuccessful procedures of assisted reproduction were analysed for cytogenetic abnormalities. A total of 12,657 metaphases from 33 individuals (15 patients and 18 healthy controls with two normal offsprings) were studied. A significantly higher incidence (P<0.001) of chromosome aberrations was found in the patients (6.79+/-0.68%; x+/-SD) as compared to the controls (1.72+/-0.3%; P<0.001). Chromosomal breakages, particularly at the centromere region, were also observed with significantly increased frequency in the patients than in the controls (6.18+/-0.65 vs. 1.42+/-0.27%, respectively; P<0.001). It is possible that the high rate of centromere breakages in the ART patients (3.18+/-0.47 vs. 0.26+/-0.12%, P<0.001) may predispose to meiotic chromosomal abnormalities. A single cell aberration was demonstrated in 0.61+/-0.21% of ART patients' lymphocytes versus 0.3+/-0.12% in the controls (P<0.01). Structural rearrangements and chromosomal breaks predominantly affected the bands containing genes for the immune response and the cell cycle. Mosaic karyotypes were found in six patients. One of them had a karyotype 46,XX/46,XX,r(14) and the others had sex chromosomal mosaicisms. The prenatal diagnosis could be essential in these cases. It is concluded that chromosomal aberrations could play a role in the repeated failure of ART procedures.

Evaluation of different ovarian stimulation protocols for in vitro fertilization

In this study we evaluated retrospectively the efficacy of five different ovarian stimulation protocols in an in vitro fertilization program, in which 512 women were involved. Ovulation was induced by the following protocols: group I (271 cycles): buserelin short protocol (1 mg/day, intranasally) with human menopausal gonadotropin/human chorionic gonadotropin (hMG/hCG); group II (45 cycles): buserelin (short protocol) with pure follicle stimulating hormone (p-FSH)/hMG/hCG; group III (24 cycles): clomiphene citrate (100 mg/day) with hMG/hCG; group IV (122 cycles): hMG (3 ampules/day) and hCG; group V (113 cycles): hMG/hCG and prednisolone (7.5 mg/day) after cycle programming with oral contraceptives. The lowest cancellation rate (3.3%) was noted in group I, followed by group V (9.7%). The highest number of follicles was observed in groups I (8.3 +/- 0.3; mean +/- SEM) and V (7.8 +/- 0.5). Also, more oocytes were retrieved in group I (7.2 +/- 0.3, p < 0.001), which were of good quality based on oocyte maturity as well as on the fertilization rate, and more embryos (4.5 +/- 0.3, p < 0.05) were developed. The correlation between estradiol and the total follicular volume on the day of hCG administration was also examined in the five groups. The best correlation (r = 0.6502) was found in group I, followed by group V (r = 0.5810). Significant differences were observed in the five groups with regard to the number of hMG ampules administered (p < 0.0001, F = 15.393) and the stimulation days (p < 0.0001, F = 35.32). Sixty-six clinical pregnancies were achieved: 37 (17.5%) in group I, seven (25.9%) in group II, one (10%) in group III, ten (15.6%) in group IV and 11 (15.5%) in group V (differences were not statistically significant). In conclusion, all five protocols were satisfactory in ovarian stimulation for in vitro fertilization, and gonadotropin releasing hormone (GnRH) analogs seemed to be more advantageous by reducing the cancellation rate, enhancing the number of oocytes retrieved and embryos developed and by improving the pregnancy rates.

Effect of follicular fluid on the kinetics of human sperm acrosome reaction in vitro

The purpose of the present study was to evaluate the kinetics of human sperm acrosome reaction in vitro using the triple stain technique. Acrosome reaction was studied in sperm samples from 16 fertile men 2, 6, and 9 h after ejaculation, following incubation in culture medium (CM; Ham's F-10), with a mixture of CM and follicular fluid (FF), or with FF only. Incubation of sperm samples without the influence of any medium served as control. The highest proportion of living acrosome-reacted sperm after a 2-h incubation period occurred in samples incubated with FF (18%), followed by samples incubated with the mixture (15.2%), and then with CM (11.8%). The proportion of living sperm that had undergone the acrosome reaction in the control group was significantly lower (5.7%, p < 0.05). After 6 h of incubation, live acrosome-reacted sperm in FF had increased to 39%, in the mixture to 35.5%, and in CM to 30.5%, whereas in the control group the increase was only 6.3% (p < 0.05). After 9 h of incubation, the percentage of living reacted sperm showed a decline compared with the percentage at 6 h. This decline was greater in samples incubated with FF (from 39 to 19.8%) than in samples incubated with the mixture (from 35.5 to 23.6%). Samples incubated in CM only showed a small decrease from 30.5 to 28.4%, while in the control group this percentage decreased from 6.3 to 2.3%. In conclusion, incubation of sperm in suitable media favorably influences the acrosome reaction, inducing an increase in the percentage of live acrosome-reacted sperm.(ABSTRACT TRUNCATED AT 250 WORDS)