PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Fertilization rate”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Fertility rates in Denmark in relation to the sexes of preceding children in the family.

Analysis of the effect of sex combination of previously born children in the family on fertility rates was performed for 363,373 Danish families comprising a total of 613,900 children, to address the questions of sex preference and combination preference. The fertility rates were stratified by parental age, period and latency time to the next child, and fertility rate ratios were estimated using multiplicative Poisson regression models. Our results demonstrate a strong preference for a balanced composition of sexes in Danish families. In families with two or three children the highest fertility rates were seen in families who had same-sexed children. The lowest fertility rates were in families with two children of identical sex followed by a child of the opposite sex. A moderate sex preference for girls was indicated by higher fertility rates in two-boy families than in two-girl families.

Birth Rate↗

[[A projection system for future age-specific fertility rates]].

"This paper presents detailed description of a newly developed fertility projection system which was used in population projections for Japan, and population projections by prefectures, officially announced in September and November 1992 respectively. The system is based on a model of age-specific fertility rates by birth order, and it converts parameters which convey behavioral traits of cohort fertility into age-specific fertility rates of future years." (SUMMARY IN ENG)

Asia↗

Experience with zona drilling and zona cutting to improve fertilization rates of human oocytes in vitro.

Zona drilling (ZD) and zona cutting (ZC) were used in an IVF programme to assist fertilization in semen defect patients. Twenty-seven patients consented to ZD where acidified Tyrode's was used to create a hole in the zona pellucida. In 19 patients, ZD increased the fertilization rate to 29% compared with 8% (P less than 0.001) in their routine IVF cycles, and in eight patients precluded from routine IVF, a fertilization rate of 14% was achieved. Twenty-two patients consented to ZC where a slit in the zona is made mechanically. In 12 patients ZC increased the fertilization rate to 31% compared with 14% (P less than 0.01) from previous routine IVF cycles, and in 10 patients precluded from routine IVF, a fertilization rate of 34% was achieved. In 13 cycles, 68 uncut control oocytes were inseminated. In five cycles both control and ZC oocytes were fertilized (n.s.d.). In eight cycles no control oocytes were fertilized compared with 27% of ZC oocytes. The polyspermy rate was 4.6%. Twenty-four per cent of ZD and 12% of ZC (P less than 0.01) oocytes and embryos were degenerate after 42 h. Both ZD and ZC can increase the fertilization rate of sub-optimal semen, however, in our hands neither technique produced a pregnancy.

Cell Survival↗

Prognostic value of first polar body morphology on fertilization rate and embryo quality in intracytoplasmic sperm injection.

The association between oocyte morphology and subsequent fertilization rate and embryo quality in intracytoplasmic sperm injection (ICSI) is subject to considerable controversy. This retrospective study was carried out to investigate a possible prognostic value of first polar body morphology with regard to fertilization rate and embryo quality. A total of 70 consecutive ICSI cases was included in this study. The results showed that classification based on first polar body morphology revealed a significant correlation with fertilization rate (P < 0.025) and embryo quality (P < 0.001). Cytoplasmic criteria showed no correlation in this respect. Present data indicate that ICSI of oocytes with intact well-shaped first polar bodies yields higher fertilization rates and higher quality embryos.

Adult↗

Individual fertility rate among minor tribal populations from Andhra Pradesh, India.

The Individual Fertility Rate (IFR), a measure of current fertility status in small and illiterate preindustrial societies, is estimated for five tribal populations from Andhra Pradesh, India. The Andhra tribes exhibit high individual fertility rates ranging between 49.62 +/- 1.76 (Konda Dora) and 66.63 +/- 3.16 (Manzai Mali) and fall in the high-fertility category. The differences in IFR values between affinal and consanguineous couples are not significant. A direct positive relation between IFR and tribal hierarchy is observed with relatively higher IFR values recorded for socially higher-ranked tribes in an ascending order from lower- to higher-ranked groups.

Adult↗

Calcium ionophore-induced acrosome reaction correlates with fertilization rates in vitro in patients with teratozoospermic semen.

The aim of this study was to determine the relationship between calcium ionophore A23187-induced acrosome reaction (AR) and sperm fertilizing ability. Semen samples remaining after preparation for standard IVF were studied in 109 patients who had sperm concentrations > or =20 x 10(6)/ml. Ionophore-induced AR was performed on motile spermatozoa selected by centrifugation on a Percoll gradient. Semen analysis was performed using standard methods. Patients with higher (>50%, n = 76) fertilization rates had significantly higher ionophore-induced AR than patients with lower (<50%, n = 33) fertilization rates (49 +/- 14 versus 38 +/- 21%, P < 0.05). When the data from all patients were analysed by logistic regression, only the percentage sperm motility in insemination medium and ionophore-induced AR were significantly related to fertilization rates. Similar results were also obtained when the data from a subgroup of patients with poor (<15% normal) sperm morphology were analysed. However, when patients with normal sperm morphology > or =15% were analysed separately, only sperm count and the percentage of spermatozoa with progressive motility in semen were significantly related to fertilization rates. In conclusion, ionophore-induced AR was significantly related to fertilization rates in vitro mainly in patients with teratozoospermic semen. Tests for ionophore-induced AR may provide additional information about sperm fertilizing ability but may not indicate specific defects of the physiological AR.

Calcimycin↗

[Consequences of oocyte dysmorphy on the fertilization rate and embryo development after intracytoplasmic sperm injection. A prospective multicenter study].

OBJECTIVES: This prospective study aimed to evaluate the impact of oocyte dysmorphy on the fertilization rate and embryonic development rate in an ICSI programme. PATIENTS AND METHODS: Three hundred and two couples have been included during 302 ICSI cycles, and 1970 oocytes have been studied in 4 ART centres. After decoronisation, 18 morphological criteria, including the size and shape of the oocyte, the thickness of the zona pellucida, the presence or not of debris in the perivitelline space, as well as the appearance of the cytoplasm and polar body have been noted. RESULTS: In total 61.3% of the oocytes presented a dysmorphy, involving, almost equally, the different oocyte compartments. Among the dysmorphic oocytes, half presented more than one anomaly. On average, 9.2% of the oocytes were lysed the day after the micro-injection. The oocytes presenting an enlarged perivitelline space, or multiple vacuoles had a significantly raised lyse rate, 16.3% and 27.8%, respectively. The day after micro-injection, 61.3% of the intact oocytes were fertilized. The rate of fertilization was correlated to the number of abnormalities per oocyte: 1 anomaly: 64.6%, > or = 3 anomalies: 54.6%. The oocytes presenting a large perivitelline space had a slightly lowered fertilization rate (53.4%). On the other hand, those showing a cytoplasm containing refractile bodies had a slightly raised fertilization rate (68.6%). We did not see any statistically significant difference between the different types of oocytes concerning embryonic development at d2. CONCLUSION: These results confirm and contribute new elements with respect to previously published data, showing that (i) oocyte morphology little affects fertilization and the first stages of embryonic development; (ii) certain dysmorphies, (enlargement of the perivitelline space) are specifically deleterious at certain stages in the process (lowering the fertilization rate); (iii) certain morphological differences (the presence of refringent bodies) are not anomalies, but can reflect physiological cellular changes.

Cell Size↗

Human chorionic gonadotrophin and steroid concentrations in follicular fluid: the relationship to oocyte maturity and fertilization rates in stimulated and natural in-vitro fertilization cycles.

The study investigates the relationship of follicular fluid steroids and human chorionic gonadotrophin to oocyte maturity and fertilization rates in stimulated and natural cycles. Oestradiol, progesterone, testosterone and human chorionic gonadotrophin were quantified in 129 samples of follicular fluid and the progesterone:oestradiol ratio calculated. Both stimulated cycles (short and long luteinizing hormone-releasing hormone/human menopausal gonadotrophin regimens) and natural cycles were compared. A total of 60 women were studied, 20 in each group. In the natural cycles, testosterone was significantly lower in follicles with intermediate oocytes (P = 0.015). Both oestradiol and testosterone were significantly lower in stimulated cycles compared to natural cycles (P = 0.032 and P = 0.034 respectively). In the ovarian stimulation cycles, the progesterone:oestradiol ratio was significantly higher when oocytes fertilized (P = 0.052). Moreover, in the stimulated cycles, oestradiol and human chorionic gonadotrophin were singnificantly lower in the short protocol compared to the long protocol. The data demonstrate that the hormonal milieu of the follicle is altered in down-regulated stimulated cycles to varying degrees, depending partially on the type of protocol used. Furthermore, the progesterone:oestradiol ratio, rather than individual hormone concentrations, may be a useful predictor of the fertilizing capacity of the oocytes.

Adult↗

Sperm immobilizing antibodies in the sera of infertile women cause low fertilization rates and poor embryo quality in vitro.

PROBLEM: The effects of sperm immobilizing antibodies in the sera of infertile women on fertilization and embryo quality in vitro were investigated. METHOD OF STUDY: Before the introduction of sperm immobilization test (SIT) as a routine test for female infertility, 85 oocytes were collected in nine in vitro fertilization (IVF) cycles from four infertile women who were afterward found having had sperm immobilizing antibodies in their sera and the oocytes were inseminated with swim-up sperm in a medium containing the patient's serum. Fifty oocytes were collected in five IVF cycles from five infertile women possessing the antibodies in their sera and the oocytes were inseminated with swim-up sperm in a medium supplemented with human serum albumin (HSA). RESULTS: In the former group, 41 of 85 oocytes were fertilized, giving a fertilization rate of 48.2%. In the latter group, 43 of 50 oocytes were fertilized, giving a fertilization rate of 86.0%. There was a significant difference of the fertilization rate between the groups (P < 0.0001). Embryo quality was assessed by the Veeck's classification. The grade 1 and grade 2 embryos were considered good quality. Using this classification, 16 (39.0%) of 41 embryos incubated in the medium containing the patient's serum were good quality, while 34 (79.1%) of 43 embryos incubated in the medium supplemented with HSA were good quality. There was also a significant difference between the groups (P = 0.0003). CONCLUSIONS: These findings might indicate that sperm immobilizing antibodies in the sera of infertile women cause low fertilization rates and poor embryo quality in vitro. It is suggested that SIT in the sera of infertile women should be performed at least before proceeding IVF. The manipulation of gametes and embryos from patients having sperm immobilizing antibodies should be carefully carried out especially to avoid contaminating patient's serum and follicular fluid in the culture medium in order to have a better IVF result.

Culture Media↗

Correlation between sperm penetration into the human zona pellucida and in vitro fertilization rates.

Sperm penetration into the zona pellucida of unfertilized oocytes, and its correlation with in vitro fertilization rates of the sibling oocytes, were assessed. This was performed in order to evaluate the prediction rate of the sperm penetration test into the zona pellucida. Unfertilized oocytes (n = 1872) from 371 cycles were pipetted through a microcapillary, and the remaining sperm cells penetrating the zona pellucida were counted. The mean (+/- SD) number of spermatozoa that penetrated the zona pellucida of unfertilized oocytes was 12.9 +/- 16.37. A significant correlation was found between the fertilization rate and the mean number of spermatozoa that penetrated into the zona pellucida of the unfertilized sibling oocytes (r = 0.48; P < 0.001), or the percent of unpenetrated zonae pellucidae in a cohort (r = -0.43; P < 0.001). However, a distinct variation in the number of spermatozoa that penetrated into the zona pellucida was detected. A step-wise regression analysis proved the number of spermatozoa penetrating the zona pellucida to be more predictive for fertilization rates than the variable of percent of unpenetrated zonae pellucidae. The results imply that although there is interdependence between penetration into the zona pellucida and fertilization rate, the predictive value of sperm penetration test for prognosis and future management after the first in vitro fertilization attempt, is limited.

Cohort Studies↗

Fertility rates with delayed fibrin glue: vasovasostomy in rats.

OBJECTIVE: To determine if fibrin glued vasovasostomy had comparable fertility rates to sutured vasovasostomy. DESIGN: Twenty adult male Sprague-Dawley rats underwent bilateral vasectomy. Two weeks after vasectomy, 10 rats had a bilateral sutured vasal anastomosis consisting of four mucosal and four seromuscular sutures with 10-0 nylon. The second group of 10 rats underwent bilateral fibrin glue vasal anastomosis consisting of two transmural sutures with 10-0 nylon followed by application of fibrin glue. One month after vasectomy reversal, each male rat was mated with a female rat for a period of 2 weeks. SETTING: Animal laboratory. PATIENTS PARTICIPANTS: Twenty male Sprague-Dawley rats. INTERVENTIONS: Bilateral vasectomies in 20 male Sprague-Dawley rats. Two weeks after vasectomy, 10 rats had bilateral sutured vasal anastomosis, and 10 rats had bilateral glued vasal anastomosis. MAIN OUTCOME MEASURES: Pregnancy after vasectomy reversal. RESULTS: Ten of 10 rats in the sutured group produced offspring for a fertility rate of 100%. Eight of 10 rats in the fibrin glue group produced offspring for a fertility rate of 80%. There was no statistically significant difference in the pregnancy rates between the two groups at the 95% confidence interval. CONCLUSION: Fibrin glue-delayed vasectomy reversal produces comparable fertility rates compared with conventional sutured vasectomy reversal in the rat.

Adhesives↗

Oocyte morphology does not affect fertilization rate, embryo quality and implantation rate after intracytoplasmic sperm injection.

In this study, we compared the fertilization rate and embryo quality after intracytoplasmic sperm injection (ICSI) as they relate to oocyte morphology. A total of 654 ICSI cycles yielding 5903 metaphase II oocytes were observed. The oocytes retrieved in these cycles were divided into (i) normal oocytes, (ii) oocytes with extracytoplasmic abnormalities (dark zona pellucida and large perivitelline space), (iii) oocytes with cytoplasmic abnormalities (dark cytoplasm, granular cytoplasm, and refractile body), (iv) oocytes with shape abnormalities, and (v) oocytes with more than one abnormality (double and triple abnormalities). Intracytoplasmic vacuoles and aggregates of smooth endoplasmic reticulum were not recorded separately. The fertilization rate and quality of morphologically graded embryos did not differ between the groups. There were 77 cycles where all transferred embryos were derived from abnormal oocytes, and 164 cycles where all embryos were derived from normal oocytes. These cycles were studied further. The two groups were comparable regarding mean female age, duration of infertility, duration of ovarian stimulation, number of ampoules of gonadotrophin injected, and number of oocytes retrieved. Two clinical pregnancy rates (44.4 versus 42.1%) and implantation rates per embryo (10.3 versus 13.2%) were similar. In conclusion, in couples undergoing ICSI, abnormal oocyte morphology is not associated with a decreased fertilization rate or unfavourable embryo quality. Furthermore, embryos derived from abnormal oocytes yield similar clinical pregnancy and implantation rates when transferred compared with embryos derived from normal oocytes.

Cell Size↗

Presence of sperm in the perivitelline space predicts fertilization rate after partial zona dissection.

OBJECTIVE: To examine the association of the number of spermatozoa present in the perivitelline space and sperm parameters with fertilization after partial zona dissection in male factor patients. DESIGN: Partial zona dissection was applied in 62 couples (84 cycles). A total of 524 oocytes underwent partial zona dissection (1/8 of the zona circumference) (partial zona dissection group) and 171 sibling oocytes were not manipulated (control group). A total of 326 manipulated oocytes were examined for the presence of spermatozoa in the perivitelline space. SETTING: University-based in vitro fertilization (IVF) program. PATIENTS: Fifty-four (87%) couples had at least one complete failure of fertilization, and 8 (13%) couples had low fertilization rate (< 10%) in previous routine IVF attempts. MAIN OUTCOME MEASURES: Fertilization rate, cleavage rate, and the number of spermatozoa present in the perivitelline space after partial zona dissection. RESULTS: Monospermic and polyspermic fertilization rates were 22.3% and 6.7% in the partial zona dissection oocytes and 8.8% and 0.6% in the nonmanipulated oocytes, respectively. The cleavage rate was similar in the partial zona dissection and control group (69.2% and 66.6%, respectively). A total of 81 partial zona dissection embryos and 10 nonmanipulated embryos were transferred to the uterus of 34 women (39 cycles), resulting in four pregnancies. In 46% (18 of 39) of the patients who had both partial zona dissection and control oocytes, only the manipulated oocytes fertilized. In only 48.8% of partial zona dissection oocytes, spermatozoa were detected in the perivitelline space; in this group of oocytes the fertilization rate was 56.6%. Sperm count and morphology were not clearly correlated with the outcome of partial zona dissection. CONCLUSIONS: The partial zona dissection technique enhances fertilization of subfertile sperm. However, the low efficiency of the procedure, apart from being associated with a high polyspermic rate, is related to the failure of sperm to traverse the slit in the zona pellucida in approximately one half of the manipulated oocytes.

Adult↗

Relationship between sperm motility assessed with the Hamilton-Thorn motility analyzer and fertilization rates in vitro.

To determine which sperm movement characteristics are related to in vitro fertilization rates, semen and swim-up preparations used for in vitro fertilization in 108 patients were assessed using the Hamilton-Thorn HTM-2030 Motility Analyzer (HTMA) and other sperm tests. There were highly significant correlations between manual and HTMA results for sperm concentration (Spearman r = 0.881; P less than 0.001) and the percentage of motile spermatozoa (Spearman r = 0.580; P less than 0.001). The percentage of motile spermatozoa with average path velocities greater than 10 microns/s and greater than 20 microns/s, straight line and curvilinear velocity, linearity (straight line velocity vs curvilinear velocity), amplitude of lateral head displacement, and beat-cross frequency were significantly higher in the insemination medium after selection of motile spermatozoa by the swim-up technique than in the semen. Linearity (P less than 0.01), the percentage of morphologically normal spermatozoa (P less than 0.05) and straight line velocity (P less than 0.05) in semen, and the percentage of motile spermatozoa with average path velocities greater than 10 microns/s in both semen (P less than 0.05) and insemination medium (P less than 0.05) were significantly correlated with in vitro fertilization rate when examined by a nonparametric (Spearman) test. With logistic regression analysis of all data, only the diagnoses of male infertility and tubal disease, linearity in semen, and the percentage of motile spermatozoa with average path velocities between 10 and 20 microns/s in insemination medium were significantly related to in vitro fertilization rates.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

Relationship of seminal traits and insemination time to fertilization rate and embryo quality.

The nature of subfertility due to the male or inseminate is as complex as that of the female. Fertilization failure or failure in embryogenesis are both documented to be of seminal origin. Males also differ in the numbers of sperm required to reach their maximum fertilization rate. Males requiring more sperm would be considered to have compensable seminal deficiencies. These include a number of known (viability and morphology) and unknown factors (functional or molecular traits) precluding sperm access to the ovum or ability to engage the ovum sufficiently to initiate fertilization and the block to polyspermy. Differences in fertility among males or inseminates independent of sperm dosage are considered uncompensable. These deficiencies would be associated with fertilizing sperm that are incompetent to maintain the fertilization process or subsequent embryogenesis once initiated, with most failures occurring prior to maternal recognition of pregnancy. Such sperm would preempt fertilization by competent sperm. Chromatin aberrations in morphologically normal or near normal spermatozoa from abnormal semen samples appear to be the best candidates for the uncompensable deficiency. However, recognition of uncompensable or incompetent fertilizing sperm has not been achieved. Six-day-old non-surgically recovered bovine ova/embryos have been used to evaluate compensable and uncompensable seminal deficiencies as well as to test reproductive strategies. These ova/embryos provide information on fertilization status and embryo quality as well as quantitative and qualitative data regarding associated accessory sperm. Thus, they permit the separation of reproductive failure by fertilization from that by embryonic development. Accessory sperm number is positively associated with both fertilization rate and embryonic quality. Early insemination results in low fertilization rates (low accessory sperm number), but good embryo quality, whereas, late insemination results in high fertilization rates (high accessory sperm number), but poor embryo quality. Additional studies will be necessary to substantiate this model; however, if true, future research designed to improve results to artificial insemination should be tested by breeding early in estrus where sperm viability is most limiting and embryo quality is best.

Animals↗

Sperm nuclear chromatin normality: relationship with sperm morphology, sperm-zona pellucida binding, and fertilization rates in vitro.

OBJECTIVE: To study whether the results of tests of sperm chromatin and deoxyribonucleic acid (DNA) normality are related to fertilization rates in vitro. DESIGN: Normal morphology, nuclear maturity determined by acidic aniline blue stain, and DNA normality determined by acridine orange fluorescence of sperm in insemination medium and the number of sperm bound to the zona pellucida (ZP) of the oocytes that had failed to fertilize in vitro were determined. The relationship between sperm test results and fertilization rates were analyzed by logistic regression. SETTING: Samples were obtained from patients undergoing in vitro fertilization (IVF) treatment. RESULTS: The number of sperm bound to the ZP, the percentage of sperm with normal morphology, and the percentage of sperm with normal DNA were the most significant factors related to fertilization rates in vitro. In patients with normal morphology > or = 15% or with > 10 sperm bound per ZP, the percentage of sperm with normal DNA, the number of sperm bound to the ZP, and motility grade were significantly related to IVF rates. CONCLUSION: In patients with normal morphology > or = 15%, failure of fertilization may be because of defects of sperm-ZP binding or abnormal DNA. Assessment of DNA normality of motile sperm in the insemination medium may aid prediction of fertilization rates in addition to normal morphology and sperm-ZP binding.

Acridine Orange↗

Statistical analysis of factors affecting fertilization rates and clinical outcome associated with intracytoplasmic sperm injection.

OBJECTIVE: To identify and evaluate the statistically significant predictors of intracytoplasmic sperm injection (ICSI) fertilization rates and clinical pregnancy in a single population using appropriate statistical techniques. DESIGN: Retrospective study. SETTING: Fertility and Endocrinology Center, University of Washington Medical Center, Seattle, Washington. PATIENT(S): Four hundred forty-one patients undergoing their first attempt at IVF-ICSI from January 1, 1999, to May 21, 2001. INTERVENTION(S): Each ICSI procedure for an individual patient was performed by a single operator. Sperm parameters, oocyte age, culture condition, ICSI technique, and ICSI operator were assessed as variables influencing the fertilization rate. We also assessed the impact of patient age, serum E(2) concentration on the day of hCG administration, embryo quality, and number of embryos transferred on the probability of achieving a clinical pregnancy. MAIN OUTCOME MEASURE(S): Fertilization rate and clinical pregnancy. RESULT(S): The 2 pronuclei (2PN) rate was significantly correlated with sperm motility, and there were significant differences in the 2PN rates among the ICSI operators. There was no difference in the 2PN rate among different sperm types or among the eight laboratory incubators or whether the eggs were cultured individually or in groups. Patient age, serum E(2) concentration on the day of hCG administration, embryo quality, and number of embryos transferred were all statistically significant predictors of clinical pregnancy. CONCLUSION(S): In our program, sperm motility and ICSI operator are the two most important predictors for the ICSI fertilization rate in vitro. Patient age, serum E(2) concentration on the day of hCG administration, embryo quality, and number of embryos transferred were all statistically significant predictors of clinical pregnancy.

Adult↗

Double-edged limit of total fertility rates.

In this paper we present the accurate estimation of total fertility rates, prove the theorem of upper and lower bounds of double-edged limit and provide the formulas of upper and lower bounds of total fertility rates. Based on these estimations and statistical data, we calculate the upper and lower bounds of the double-edged limit for 46 countries including China. Furthermore, we describe the positive growth rate, negative growth rate and zero growth rate of population development. These results are of great importance for us to control population not only in theory but also in practice.

Fertility↗