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PubMed1996

The effect of antioxidant treatment on human spermatozoa and fertilization rate in an in vitro fertilization program.

OBJECTIVE: To study the possible influence of antioxidant treatment on human spermatozoa and the fertilization rate in an IVF program. DESIGN: Prospective study. SETTING: In Vitro Fertilization Unit, Serlin Maternity Hospital, and the Laboratory of Male Fertility, Bar-Ilan University, Ramat-Gan, Israel. PATIENTS: Fifteen fertile normospermic male volunteers who had low fertilization rates in their previous IVF cycles. INTERVENTIONS: Vitamin E (alpha-tocopherol) 200 mg daily by mouth for 3 months. MAIN OUTCOME MEASURES: Lipid peroxidation potential (amount of malondialdehyde [MDA]), quantitative ultramorphologic analysis of spermatozoa, and fertilization rate per cycle. RESULTS: The high MDA levels significantly decreased from 12.6 +/- 9.4 nmol/10(8) spermatozoa to normal levels of 7.8 +/- 4.2 nmol/10(8) spermatozoa after 1 month of treatment. The fertilization rate per cycle increased significantly from 19.3 +/- 23.3 to 29.1 +/- 22.2 after 1 month of treatment. No additional effects on MDA levels and fertilization rate were observed after completion of treatment. With regard to the quantitative ultramorphologic analysis, none of the sperm cell subcellular organelles were affected significantly by vitamin E treatment. CONCLUSION: Vitamin E may improve the fertilization rate of fertile normospermic males with low fertilization rates after 1 month of treatment, possibly by reducing the lipid peroxidation potential, and with no change of the quantitative ultramorphologic analysis of subcellular organelles.

Administration, Oral↗
PubMed1985

The relationship of semen parameters to fertilization in patients participating in a program of in vitro fertilization.

Approximately 80% of the patients in a program of in vitro fertilization (IVF) will fertilize an oocyte. The purpose of this study was to determine which parameters of the semen analysis influence fertilization in vitro. Of 120 patients participating in an in vitro fertilization program, 98 achieved fertilization of at least one mature oocyte and 22 did not. Ovulation induction was standardized and patients whose sperm was exposed to at least one mature oocyte (by light microscopy) were included in the study. Semen washing was accomplished using a "swim-up" technique. Semen parameters were assessed both before (raw) and after washing. Following insemination with 100,000 motile sperm, fertilization was determined by the presence of pronuclei or cleavage. Mean sperm count and motility were higher in patients who fertilized. However, morphology was similar. Fertilization was more likely to occur with a raw density greater than 104 million/ml and a motility greater than 64%, as well as with a density greater than 18 million/ml and a motility greater than 86% following washing. Furthermore, washing lowered sperm counts by 75% and increased motility by 25% but had no effect on morphology. This study demonstrates that sperm count and motility, but not morphology, influence fertilization in a program of in vitro fertilization and that patients with higher counts and motility have a greater probability of fertilization.

Female↗
PubMed1994

Pregnancy and birth rates of live infants after in vitro fertilization in women with an without previous in vitro fertilization pregnancies: a study of eight thousand cycles at one center.

OBJECTIVE: Our aim was to compare the cumulative conception and live-birth rates after in vitro fertilization in women undergoing their first course of in vitro fertilization treatment with those in women undergoing their second course of treatment, having previously achieved an in vitro fertilization pregnancy. This study occurred in a tertiary referral-assisted conception unit. STUDY DESIGN: The cumulative conception rates obtained by life-table analysis in 4115 women having their first course of in vitro fertilization therapy (7327 treatment cycles leading to 1123 pregnancies) were compared by means of the log-rank test with those of 331 women in their second course of treatment, having previously achieved an in vitro fertilization pregnancy (561 treatment cycles leading to 138 second in vitro fertilization pregnancies). Similarly, the cumulative live birth rates of 3824 women in their first course of treatment (7136 treatment cycles leading to 732 live births) were compared with those of 105 women in their second course of treatment, having previously achieved an in vitro fertilization live birth (205 treatment cycles leading to 33 second in vitro fertilization live births). RESULTS: The cumulative conception rates and cumulative live birth rates were significantly higher in women having their second course of in vitro fertilization treatment than in those having their first course (cumulative conception rate: p = 0.0001; cumulative live birth rate, p = 0.007). After five cycles of in vitro fertilization, the cumulative conception rates and cumulative live birth rates were 49.8% (95% confidence interval, 46.3% to 53.5%) and 39.0% (95% confidence interval, 35.4% to 42.9%), respectively, in those having their first course of treatment compared with 69.9% (95% confidence interval, 57.6% to 81.3%) and 68.6% (95% confidence interval, 46.1% to 88.5%), respectively, in those having their second course. The estimated median numbers of cycles taken to achieve a pregnancy and live birth (assuming all women could potentially undergo the same number of cycles) were six and eight, respectively, in the first course of treatment compared with only three and five in the second course. CONCLUSION: Women who have achieved a previous in vitro fertilization pregnancy have significantly higher cumulative conception rate and cumulative live birth rates compared with those of women having their first course of treatment.

Adult↗
PubMed2000

Defective sperm-zona pellucida interaction: a major cause of failure of fertilization in clinical in-vitro fertilization.

Sperm-zona pellucida binding and penetration were assessed on the oocytes that failed to fertilize from couples with >/=3 oocytes treated by standard in-vitro fertilization (IVF). There were four groups: fertilization rate 0% (n = 369), 1-25% (n = 194), 26-50% (n = 81) and 51-95% (n = 100). Of the couples with zero fertilization rate 70% had </=5 spermatozoa bound per zona pellucida and 42% had no spermatozoa penetrating the zona pellucida of any oocyte. In contrast, in the 51-95% fertilization rate group, only 17% had </= 5 spermatozoa bound per zona pellucida and 6% had no spermatozoa penetrating the zona pellucida. There was a significantly higher frequency of poor sperm morphology (</= 5% normal) in couples with zero fertilization rate (36%) than in the fertilization rate group 51-95% (7%). Incubation of oocytes from 68 couples with zero fertilization rate and low sperm-zonae pellucidae binding with fertile donor spermatozoa resulted in normal sperm-zona pellucida binding and most zonae pellucidae being penetrated. In conclusion, defective sperm-zona pellucida interaction was the major cause for low fertilization rates in standard IVF. This was usually because of defects of the spermatozoa rather than defects of the oocytes. Sperm defects likely to cause failure of fertilization should be diagnosed before commencing IVF and the patients directed to intracytoplasmic sperm injection.

Female↗
PubMed1986

Fertility of cooled and frozen rabbit sperm measured by competitive fertilization.

The fertility of rabbit sperm that had been cooled to 5 degrees C or frozen and thawed was determined by competitive fertilization. Treatments were identified by labeling sperm with fluorescein isothiocyanate (FITC) or tetramethylrhodamine B isothiocyanate (TRITC). Sperm from different treatments were mixed and used in a competitive insemination experiment. Does were inseminated 5, 10 or 15 h prior to ovulation. Time of ovulation was controlled by injections of luteinizing hormone. The functional sperm transport, as determined by the number of sperm transported to the site of fertilization and capable of fertilizing oocytes, was estimated by counting the total number of differently stained sperm that surrounded or fertilized each oocyte. The fertility of sperm cooled to 5 degrees C was not affected (p less than 0.05) as compared to fertility of uncooled sperm. Functional sperm transport at all times of insemination and fertilization ratio at insemination 10 or 15 h before ovulation were reduced (p less than 0.05) for frozen-thawed vs. cooled sperm. No difference in fertilization ratio (p greater than 0.05) occurred, however, when does were inseminated 5 h before ovulation. While sperm survival and capacitation time appeared to play roles in fertility of frozen-thawed sperm, the most important factor was reduced functional sperm transport. However, fertility of frozen-thawed sperm was improved when the time from insemination to ovulation was reduced.

Animals↗
PubMed1994

[The rate of polyploid fertilization of ovocytes in in vitro fertilization in patients with an increased ovarian response].

Polyploid fertilization is a common cause of human embryo's early loss in in vivo (1-2%) and in in vitro fertilization (3-5%) as well. Cause of increased rate of polypoid fertilization in in vitro fertilization is multifactorial. The aim of this paper was to establish if high ovarian response to exogenous hormone stimulation of ovaries can be one of the causes of increased incidence of polyploid fertilization. The research included 125 patients from whom 568 ovocytes were obtained by ultrasound aspiratory punction of ovarian follicles. The gathered results point to the fact that exogenous ovarian stimulation and the degree of ovarian response have a significant influence on increase of polyploid fertilization's rate. Thus, in the group of patients from whom 11 or more ovocytes were obtained, the rate of polyploid fertilization amounted to 11.3%, whereas it is statistically significantly higher (p < 0.01) in regard to those in whom less important difference in the rate of polyploid fertilization considering applied schemes of ovulation's stimulation (p > 0.1) was not established nor was it established considering the age of patients (p > 0.05). Despite the fact that the rate of polyploid fertilization in in vitro conditions is higher that in the natural conception, this method of treating marital infertility opens a unique possibility to identify all irregularities considering fertilization and prevent development of such embryos on time as it happens at the very beginning of the preimplantational stage of ovum's fertilization in laboratory conditions.

Adult↗
PubMed1981

[Studies of fertilizing capacity of spermatozoa from infertile men with oligozoospermia. AIH by washed and concentrated spermatozoa and in vitro fertilizing capacity to zona free hamster eggs (author's transl)].

The fertilizing abilities of spermatozoa from infertile men with oligozoospermia were evaluated by examining pregnancy rates after AIH using washed and concentrated spermatozoa, and also by in vitro fertilizing rates to zona free hamster eggs. The spermatozoa from ten oligozoospermic men with less than 20 x 10(6)/ml of sperm counts were used in the experiments. After the procedures of washing and concentrating spermatozoa from oligozoospermic men, the sperm concentration was increased from two to six times and the sperm motility was also increased up to two times. However none of the patients' wives conceived after several AIHs with washed and concentrated spermatozoa. When the in vitro fertilization of zona free hamster eggs by the spermatozoa was used, the fertilization rates were null in case of 7 oligozoospermic patients, and 5, 10 and 33.3% in case of another 3 oligozoospermic patients respectively in contrast with 73.3% in use of spermatozoa from control fertile men. The fertilizing abilities of spermatozoa from husbands of 4 sterile couples with an unknown cause were examined by in vitro fertilization test and 7.1, 37.5, 50.0 and 55.6% fertilization rates were obtained. Among these men, the spermatozoa from one man indicated a very low fertilization rate without any other pathological findings. This suggests that the impairment of fertilizing ability of spermatozoa might be present in the case of sterile men with an unknown cause.

Adult↗
PubMed1990

Temporal dimensions of the fertility transition: an age-period-cohort analysis of frontier fertility.

"This paper evaluates age, period, and cohort effects on marital fertility during onset of the Utah fertility transition (1880-1900). Computerized genealogies are used to derive age-period-cohort fertility rates for 49,842 once-married couples. Age, period and cohort effects on marital fertility are then estimated using Johnson's (1985) relational model. Declining marital fertility in Utah is shown to be explained by both lower fertility levels across periods and increasing age-specific limitation across cohorts. Direct cohort effects on fertility are insignificant. These results are consistent with prior research, and the view that fertility levels were adaptive (in part through birth spacing across ages) to immediate contexts of childbearing while age-specific fertility truncation increased across cohorts (in part through the more general diffusion of contraceptive innovations)."

Age Factors↗
PubMed1990

The use of rat in vitro fertilization to detect reductions in the fertility of spermatozoa from males exposed to ethylene glycol monomethyl ether.

An in vitro fertilization (IVF) assay sensitive enough to detect changes in the fertilizing capacity of spermatozoa would be a useful tool with which to investigate the action of testicular toxicants. A known testicular toxicant, ethylene glycol monomethyl ether (EGME), was used to induce specific lesions in the germinal epithelium so that the ability of a rat IVF system to detect changes in fertility could be tested. Male rats were given single, oral doses of 50, 100, and 200 mg EGME/kg. Spermatozoa were recovered from the cauda epididymides of these males at intervals after treatment; their fertility was assessed using IVF, and the testes were processed for histologic examination. The fertility of the control males was consistently greater than 65%. Spermatozoa from males treated with EGME had reduced fertility at specific times after dosing. Thus, after 50 mg EGME/kg there was reduced fertility at 5 weeks; after 100 mg EGME/kg there was reduced fertility at 3.5, 4.5, 5, 6, and 6.5 weeks, and after 200 mg EGME/kg there was reduced fertility at 2 and 3 weeks, between 4.5 and 6 weeks, and at 7 weeks. This corresponded to damage to the elongated spermatids (2, 3, and 3.5 weeks), pachytene spermatocytes (4.5 to 6 weeks), and leptotene and preleptotene spermatocytes (7 weeks). This accords well with the data from serial breeding trials and reports of histologic damage after exposure to EGME. Therefore, using IVF it was possible to detect EGME-induced changes in fertilizing capacity which correlated closely with observations of testicular damage. It was also possible to demonstrate a clear dose response to EGME.

Animals↗
PubMed1999

Intracytoplasmic sperm injection overcomes previous fertilization failure with conventional in vitro fertilization.

OBJECTIVE: To evaluate the outcome of intracytoplasmic sperm injection (ICSI) in patients with previous idiopathic fertilization failure (< or =20% fertilization rate) after conventional IVF. DESIGN: Retrospective analysis. SETTING: IVF program at a university medical center. PATIENT(S): Twenty-five patients who underwent 38 ICSI cycles after experiencing unexplained fertilization failure with conventional IVF (group A) and 87 patients who underwent 118 ICSI cycles for male factor indications during the same period (group B). INTERVENTION(S): Intracytoplasmic sperm injection was performed in a subsequent cycle after fertilization failure with conventional IVF. MAIN OUTCOME MEASURE(S): Outcomes of IVF were compared between groups A and B. RESULT(S): Fertilization was achieved with ICSI in all patients with previous fertilization failure. The mean (+/- SD) fertilization rate (68%+/-21% vs. 64%+/-22%), implantation rate per embryo (22.6% vs. 20%), and delivery rate per cycle (47.3% vs. 49.1%) did not differ significantly between groups A and B. Overall, 72% of patients with previous unexplained fertilization failure had a successful pregnancy after ICSI. CONCLUSION(S): Intracytoplasmic sperm injection can overcome unexplained fertilization failure caused by a potentially occult gamete abnormality, with the same fertilization, implantation, and pregnancy rates as are seen in patients with abnormal sperm parameters.

Adult↗
PubMed1995

Cryopreservation of human oocytes and fertilization by two techniques: in-vitro fertilization and intracytoplasmic sperm injection.

Human oocyte cryopreservation results in poor survival and subsequent fertilization rates. It has been suggested that freeze-thaw-induced changes in the zona pellucida may impair sperm penetration or attachment. The aim of this study was to compare fertilization and cleavage rates in cryopreserved oocytes inseminated by conventional in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). A total of 220 oocytes, obtained from volunteers who had undergone ovarian stimulation, were cryopreserved using a slow freeze-rapid thaw protocol with 1.5 M propanediol as the cryoprotectant. Surviving oocytes (n = 74, 34.4%) were randomly allocated for fertilization by conventional IVF (group 1) or ICSI (group 2) using cryopreserved spermatozoa from a single donor of proven fertility. Fertilization was achieved in five (13.5%) of the oocytes in group 1 and 17 (45.9%) in group 2 (P < 0.005), with only one oocyte in group 1 exhibiting normal fertilization as opposed to 16 (43.2%) in group 2 (P < 0.001). Similarly, one oocyte fertilized by IVF cleaved, while all fertilized with ICSI cleaved (P < 0.001). We conclude that although the survival of oocytes is poor following cryopreservation, fertilization and cleavage rates can be enhanced significantly using ICSI. These data also suggest that the method of cryopreservation used in this study affected the zona pellucida, such that normal sperm attachment or penetration was impaired.

Cleavage Stage, Ovum↗
PubMed1994

Experience with assisted fertilization in severe male factor infertility and unexplained failed fertilization in vitro.

We present results of in-vitro fertilization (IVF) cycles using assisted fertilization at our centre. Assisted fertilization was performed in those couples who had failed to fertilize oocytes with conventional IVF, or where this was predicted by the presence of severe male factor infertility. In 20 consecutive assisted fertilization cycles 223 oocytes were subjected exclusively to subzonal insemination (SUZI). Subsequently in 32 consecutive assisted fertilization cycles 418 oocytes were subjected to intra-cytoplasmic sperm injection (ICSI). More oocytes were damaged by ICSI (8.9%) than by SUZI (2.3%) (P = 0.03), but normal fertilization resulted more often after ICSI (56.9%) than SUZI (35.8%) (P = 0.004). Sperm parameters, other than sufficient numbers to perform the procedures, had no effect on fertilization or pregnancy rates. Every cycle led to the transfer of at least one embryo. Pregnancy resulted from eight of the SUZI cycles (40%) and nine of the ICSI cycles (28%). Implantation rates were calculated as 25 and 12% for SUZI and ICSI respectively. The presence of living spermatozoa is the only semen parameter limiting assisted fertilization. At present more centres are able to perform SUZI than ICSI and we feel it is premature to abandon SUZI altogether. Local conditions and success rates should be considered when decisions are made in assisted fertilization cycles.

Adult↗
PubMed1989

Relationship of bull fertility with daughter fertility and production traits in Holstein dairy cattle.

The phenotypic and genetic correlations between fertility ratings of AI bulls for conception rate and their estimated breeding values for daughters' fertility and production traits were calculated. Genetic correlations between fertility ratings of bulls for conception and heifer fertility traits (age at first breeding, age at last breeding, and number of insemination per conception) were negative and ranged from -.04 to -.23, indicating daughters of bulls with high fertility ratings were younger at first breeding and required fewer services to conceive. In general, genetic correlations between fertility ratings of bulls for conception rate and cow fertility traits (days from calving to first breeding, days open, and number of inseminations per conception) and production traits (breed class average milk and fat and fat percentage) in the first two lactations were also moderate to high and in the favorable direction. Although heritability of both male and female fertility is low, these data indicate that heavy use of sires with high fertility ratings could have a mild positive effect on both male and female fertility. Evidence is also found to indicate that in this breed, selection for increased milk yield should not impair genetic ability of cows to reproduce.

Animals↗
PubMedDate not supplied

Hemizona index (HZI) demonstrates excellent predictability when evaluating sperm fertilizing capacity in in vitro fertilization patients.

The objective of this work was to assess the power of the hemizona assay to predict in vitro fertilization (IVF) results using receiving operating characteristics (ROC) analysis. In a tertiary medical center setting, 94 couples undergoing IVF were included in the study comparing their fertilization results to sperm function during the hemizona assay. Using ROC analysis, fertilization in IVF (mature oocytes only) was compared to performance of the sperm in the sperm-zona pellucida binding test as expressed by hemizona index (HZI; [number of test sperm bound/number of control sperm bound] x 100). The IVF results were as follows: 32 patients had no fertilization (0%), 55 patients fertilized all of the oocytes (100%), and 7 patients fertilized between 14% and 85% of the oocytes. Modified ROC analysis was used to determine the best threshold for fertilization success or failure, depending upon how the data are viewed. A HZI of 40-43 separated the 100% fertilization group from the other groups, with a true positive rate of 87% and a true negative of 83%. Conversely, a HZI of 4-5 separated the 0% fertilization versus partial or total fertilization, with a true positive rate of 100% and true negative rate of 71%. Sperm performance in the hemizona assay as measured by the HZI reflects performance in IVF and benefits couple evaluation and counseling.

Female↗
PubMed2000

Rescue intracytoplasmic sperm injection (ICSI)-salvaging in vitro fertilization (IVF) cycles after total or near-total fertilization failure.

OBJECTIVE: To evaluate the effectiveness of delayed oocyte reinsemination by ICSI (rescue ICSI) after total or near-total fertilization failure (</=25%) in IVF. DESIGN: A retrospective clinical study. SETTING: Non-hospital-based IVF program. PATIENT(S): Thirty IVF cycles with total fertilization failure and two cycles with </=25% initial fertilization. MAIN OUTCOME MEASURE(S): Fertilization and pregnancy rates after rescue ICSI. INTERVENTION(S): Rescue ICSI 19-22 hours after initial oocyte insemination. RESULT(S): A fertilization rate of 60.2% was achieved with rescue ICSI (141 of 234 oocytes, 29 of 32 patients). Of 30 patients with total fertilization failure, 27 had fresh transfers with rescue ICSI embryos. Two additional patients with </=25% initial fertilization had subsequent replacement of frozen-thawed rescue ICSI embryos. Six pregnancies resulted, including three singleton, one twin, one missed abortion, and one ectopic pregnancy (20.7%). One of the singleton pregnancies resulted from replacement of four frozen-thawed embryos and is the first known pregnancy achieved from cryopreserved rescue ICSI embryos. CONCLUSION(S): Rescue ICSI should be considered in the presence of total or near-total fertilization failure in IVF. Early application of rescue ICSI (19-22 hours after insemination) may be critical for establishing fertilization within an optimal window and producing viable embryos and pregnancies.

Adult↗
PubMed1996

Evaluation of a cut-off value for normal sperm morphology using strict criteria to predict fertilization after conventional in-vitro fertilization and embryo transfer in asthenozoospermia.

The predictive value of sperm morphology evaluation using strict criteria (MEUSC) on fertilization and pregnancy rates was evaluated in 60 couples undergoing in-vitro fertilization (IVF) and embryo transfer. In all, 47 of the male partners had a progressive sperm motility < 50% with a density > 20 x 10(6)/ml (asthenozoospermia) and 13 had normozoospermia. MEUSC was performed on the same semen sample that was used for IVF on at least 100 spermatozoa after Papanicolaou staining at x 1250 magnification. Defects in the head, mid-piece and tail were counted separately, borderline forms were classified as abnormal and the teratozoospermia index was calculated for each sample. Of the spermatozoa in the asthenozoospermic group, 13.0% were judged as normal on MEUSC versus 19.8% in normozoospermia (P = 0.0013). The number of normal spermatozoa on MEUSC correlated with the progressive motility in asthenozoospermia (rho = 0.41, P = 0.0043). Defects in the mid-piece (P = 0.0004) and tail (P = 0.025) were more common, and the teratozoospermia index (P = 0.015) was higher in asthenozoospermic than normozoospermic samples. The parameters of MEUSC did not correlate with the fertilization rate. In asthenozoospermia, differences in fertilization rates were calculated for each cut-off value between 4 and 10% normal spermatozoa on MEUSC. A cut-off value of 6% gave the best statistical power. If > 6% of spermatozoa were normal, a median of 66.7% of ova were fertilized, compared with a median fertilization rate of 35.4% if < or = 6% of spermatozoa were normal (P = 0.022). The highest cut-off value still giving significant discrimination was 8% (normal MEUSC > 8%, median fertilization rate 66.7%; < or = 8%, median fertilization rate 35.7%, P = 0.028), and this may be used as the critical value for normal morphology in asthenozoospermia. It is concluded that despite a significant linear relationship between morphology using strict criteria and progressive motility, MEUSC is still useful as a predictor for fertilization in asthenozoospermia. In cases of asthenozoospermia with < or = 8% normal spermatozoa on MEUSC, micromanipulation should be considered.

Adult↗
PubMed2002

In vitro fertilization of in vitro-matured equine oocytes: effect of maturation medium, duration of maturation, and sperm calcium ionophore treatment, and comparison with rates of fertilization in vivo after oviductal transfer.

Three experiments were conducted to evaluate the effect of oocyte and sperm treatments on rates of in vitro fertilization (IVF) in the horse and to determine the capacity of in vitro-matured horse oocytes to be fertilized in vivo. There was no effect of duration of oocyte maturation (24 vs. 42 h) or calcium ionophore concentration during sperm capacitation (3 microM vs. 7.14 microM) on in vitro fertilization rates. Oocytes matured in 100% follicular fluid had significantly higher fertilization (13% to 24%) than did oocytes matured in maturation medium or in 20% follicular fluid (0% to 12%; P < 0.05). There was no significant difference in fertilization rate among 3 sperm treatments utilizing 7.14 microM calcium ionophore (12% to 21%). Of in vitro-matured oocytes recovered 40-44 h after transfer to the oviducts of inseminated mares, 77% showed normal fertilization (2 pronuclei to normal cleavage). Cleavage to 2 or more cells was seen in 22% of oocytes matured in follicular fluid and 63% of oocytes matured in maturation medium; this difference was significant (P < 0.05). We conclude that in vitro-matured horse oocytes are capable of being fertilized at high rates in the appropriate environment and that in vitro maturation of oocytes in follicular fluid increases fertilization rate in vitro but reduces embryo development after fertilization in vivo. Further work is needed to determine the optimum environment for sperm capacitation and IVF in the horse.

Animals↗
PubMed2003

[Fertilization rate analysis as a predictive variable for an in-vitro fertilization program success].

OBJECTIVE: Determining if fertilization rates can be used as a predictive factor for pregnancy induction in ETIVF-ICSI programs. TYPE OF STUDY: Retrospective, observational and descriptive. MATERIALS AND METHODS: Six hundred and seventy nine cycles of the in vitro fertilization program, using long protocol hypophyseal suppression, stop, or antagonsits, were included. Ovarian stimulation was carried out with menotropines or recombinant FSH. Those patients whose cycle was stopped due to the lack of follicular development were excluded. Variables under study were: age, fertilization percentage, pregnancy rate, pre-ovulatory estradiol levels, number and quality of captured oocytes, transferred embrios and endometrial thickness on the day of transference and the presence of pregnancy. The Pearson P Test with a 95% confidence interval and the Student T Test used to establish differences with a 95% confidence interval statistical analyses were applied. RESULTS: Six hundred and seventy nine cycles were studied, 487 of which used the conventional fertilization method, and 192 used the ICSI method. Mean age among patients was 34 +/- 1.1 years old, with pre-ovulatory estradiol levels of 4,023 +/- 1,134 pg/mL, the average quantity of captured oocytes was 11.7 +/- 3.2 with a capture rate of 69.6%. Mean fertilization rates averaged 54% with a 20.7% pregnancy rates using the transference method. After analyzing the fertilization rate in each group, a statistically significant linear correlation was observed (P = 0.547, CI 95%) with the pregnancy rate. After assigning patients to two different groups: conventional IVF and ICSI, a higher positive correlation was observed (P = 0.827, CI 99%) in the first group. No significant differences were observed in the remaining parameters between both groups, excepting oocyte maturity, where greater prophase I and metaphase II percentages were observed in the ICSI group. When 50% fertilization was taken as the cutting point, a 78.19% negative predictive value was determined, with a 25% positive predictive value, 77.5% sensitivity, and 25.6% specificity. CONCLUSIONS: A fertilization percentage greater than 50% can be used as a pregnancy predicting factor in in vitro fertilization programs.

Adult↗