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PubMed1983

[Continuous ecopathological survey. 2. Typology of dairy cattle farms with high and low fertility].

Management characteristics were analysed in two groups of dairy herds (20 to 60 cows per herd) during a continuous eco-pathological survey, in relation to high and low fertility. 59.8% of the cows from the eleven high fertility herds were successfully inseminated at first service and 11.4% of the cows inseminated for the first time more than 40 days post-partum required 3 or more services. The corresponding values were 51.1 and 25.6% for the ten low fertility herds. Other reproductive criteria (calving-first service interval, disturbed oestrus cycles), which more depend on the reproduction management, were not different between the two groups. Feeding system greatly varied in the low fertility group. Frequent changes in diet composition, a longer period of "green" forages distribution (crucifers, grass silage) as well as less utilisation of concentrates are some of the reasons which can explain the low fertility. Calving occurred mainly from February to April in low fertility herds, at the transition from winter diets to grazing. Milk production was lower, 4 580 kg per cow and per year vs 5 520 kg for high fertility group. Milk production falls were more frequent and Holstein semen was less used. Tied housing conditions, and higher incidence of Fasciola hepatica and abomasal mematodes characterised low fertility herds; inversely, the clinical pathology appeared to be less frequent in this group. Soil manganese concentration was lower (16.3 ppm) in the low fertility group as compared to the other group (30.9 ppm); this could be explained by less schistose rocks where the low fertility farms are localized. In conclusion, the risk factors associated with low fertility may be attributed to: the composite system of feeding in addition to the use of "green" forages, a lack of proper programming with regards to the season of calving, and the high frequency of parasitic infestations, with special reference to liver fluke.

Animals↗
PubMed2000

Premarital fertility in rural South Africa: a challenge to existing population policy.

The age pattern of fertility in a rural area of South Africa under demographic surveillance (Agincourt subdistrict) was investigated over the 1992-97 period. The total fertility rate (TFR) averaged 3.3 births per woman of reproductive age over the period, a major drop from earlier estimates in the same area (6.0 births in 1970-74). Age-specific fertility rates showed an atypical bimodal pattern. They were decomposed into two components of similar magnitude: premarital fertility (among women aged 12-26) and marital fertility (among women aged 15-49). The decomposition revealed the two underlying modes: a mode of premarital fertility (among women aged 18-20) and a mode of marital fertility (among women aged 28-30). Premarital fertility accounted for 21 percent of all births and for 47 percent of births among women aged 12-26. This pattern of high premarital fertility appears to reflect a low incidence of contraceptive use before the first birth, especially among adolescents, a low prevalence of abortion, and a high contraceptive prevalence thereafter. This finding calls for a reorientation of the family planning policy, which until now has targeted married women and women who have been pregnant once, but has failed to address the contraceptive needs of young women before their first pregnancy, especially adolescents.

Adolescent↗
PubMed1992

Analysis of factors contributing to fertility decline in Korea.

With the successful Korean national family planning program and rapid socioeconomic advancement since 1962, the contraceptive prevalence rate has risen from 9% in 1964 to 79% in 1991, with the corresponding total fertility rate (TFR) going from 6.0 in 1960 to 1.6 in 1988, which is considerably below the replacement fertility rate. The main purpose of this study is, therefore, to identify the structural and causal factors that contributed to the fall in fertility over the last 3 decades, in an effort to formulate future population policy directions and strategies. The 2 methods used for the study were: the standardization approach to examine the structural factors on fertility decline, and the bongaarts model to measure the effects of the proximate variables in the fertility decline. The study indicated that the fall in the crude birth rate and the general fertility rate for the periods of 1960-70 and 1980-90 were largely influenced by the decline in marital fertility which was triggered by the national family planning program initiated in 1962. The analysis based on the bongaarts model revealed that the 3 principal factors which exercised a strong influence on the fertility decline were the rise in age at marriage, the increase in induced abortion, and the increase in contraceptive use, but the influence of induced abortion has been decreasing in recent years. In general, the study results suggest that the main concerns of the national family planning program should be shifted from the past quantitative approach with emphasis on fertility reduction to a qualitative approach which stresses maternal and child health and other public health programs.

Abortion, Induced↗
PubMed1994

Seasonal biochemical changes in coniferous forest canopies and their response to fertilization.

Seasonal changes in concentrations of total nitrogen, free amino acids, chlorophyll, starch and sugar were measured in foliage from fertilized and unfertilized conifer forests in New Mexico and Oregon. In the New Mexico Douglas-fir (Pseudotsuga menziesii var glauca (Beissn.) Franco) forest, fertilization resulted in elevated foliar nitrogen concentrations on all dates, from an average of 9 mg g(-1) in unfertilized trees to 14 mg g(-1) in fertilized trees. In the Oregon western hemlock (Tsuga heterophylla (Raf.) Sarg.) forest, fertilization increased total N by only 15%, from 13 mg g(-1) in unfertilized trees to 15 mg g(-1) in fertilized trees. Foliar nitrogen concentrations on a weight basis were lowest in winter and spring, but did not vary seasonally when expressed on a leaf area basis. Chlorophyll concentrations increased with fertilization and had greater seasonal variation than did total nitrogen concentrations. Chlorophyll concentrations were significantly higher during the growing season than in the winter and spring months. Fertilization did not result in major changes in the proportion of total nitrogen in chlorophyll at either the Oregon or the New Mexico site. Concentrations of free amino acids varied with date and fertilization treatment; in New Mexico, amino acids were highest in the winter sample, whereas in Oregon, they were lowest in winter and spring. At both sites, amino acid concentrations were significantly higher in fertilized trees than in control trees on most dates and the ratios of amino acid-N to total N were also significantly higher in fertilized trees. For both sites, starch concentrations were nearly zero for most of the year, but increased sharply just before bud break and initiation of new growth in the spring. Although fertilization resulted in increased nitrogen concentrations in foliage at both sites, the response in New Mexico was much greater than in Oregon. These results are in agreement with forest productivity data that suggest that growth in the New Mexico site is limited by nitrogen, whereas in the Oregon site it is not.

Journal Article↗
PubMed1995

Variation in the ratio of shoot silhouette area to needle area in fertilized and unfertilized Norway spruce trees.

We compared the range and variation in shoot silhouette area to projected leaf area ratio (SPAR) in fertilized and unfertilized (control) Norway spruce (Picea abies (L.) Karst.) trees. We measured SPAR for several view directions of 169 shoots at different depths in the crown of fertilized and control trees. There was an increase in SPAR with depth in the crown in both control and fertilized trees. In the fertilized trees, however, mean SPAR was larger overall, the increase with depth in the crown was steeper, and there was a larger variation in SPAR with inclination and rotation angle of the shoot (relative to the view direction). In particular, shoots in the lower crown of fertilized trees were rotationally asymmetrical ("flat") and had high values of the maximum ratio of shoot silhouette area to projected leaf area (SPAR(max)). Differences in SPAR between fertilized and control trees were explained by changes in shoot structure in response to fertilization and shading. Shoots of fertilized trees were larger and had more needle area than shoots of control trees. However, the ratio of needle area to shoot size was smaller in fertilized trees than in control trees, implying less within-shoot shading and, consequently, a larger SPAR. Also, the increase in SPAR with increased shading (depth in the crown) could be explained by a decrease in the ratio of needle area to shoot size. In addition, because fertilized trees had more needle area than control trees, the effect of shading at a given depth in the crown was more pronounced in fertilized trees than in control trees.

Journal Article↗
PubMed1998

Evaluation of prostaglandin F2 alpha treatment in dairy cows at risk for low fertility after parturition.

OBJECTIVE: To evaluate the effect of 2 postpartum prostaglandin F2 alpha (PGF 2 alpha) treatment protocols on reproductive performance of dairy cows at risk for low fertility. In addition, various medical conditions in cows that are recognized as having adverse effects on fertility were evaluated as criteria for fertility treatment. DESIGN: Prospective study. ANIMALS: 291 cows with, and 271 cows without, risk factors for low fertility. PROCEDURE: Cows at risk for low fertility were randomly assigned to 2 treatment groups. Group-1 cows received 3 i.m. injections of PGF2 alpha at weekly intervals after parturition, and group-2 cows received 1 i.m. injection of PGF2 alpha 17 to 24 days after parturition. RESULTS: Compared with a single PGF2 alpha treatment 17 to 24 days after parturition, there was no added benefit of 3 treatments with PGF2 alpha 3 to 10, 10 to 17, and 17 to 24 days after parturition in cows at risk for low fertility. Cows without risk factors for low fertility had 20% higher pregnancy rates, compared with cows with risk factors for low fertility. Twinning had a negative effect on future fertility. CLINICAL IMPLICATIONS: Results of this study indicate that further consideration should be given to the timing and intervals of PGF2 alpha administration after parturition. Risk factors for low fertility, such as retained placenta, twins, and assisted calvings, are valid criteria to evaluate different treatment options to improve fertility in dairy cows.

Animals↗
PubMed1979

Cytological events associated with in vitro aged and fertilized rabbit eggs.

The morphogenetic events associated with rabbit eggs aged in vitro for 12 to 50 hours prior to mixing with sperm have been examined by light and electron microscopy. After 12 hours in culture, morphological alterations of the meiotic spindle and the cortex of unfertilized eggs were evident. By 24 to 50 hours in culture, unfertilized eggs contained subnuclei, structures which formed when individual and/or groups of meiotic chromosomes dispersed and becmae invested by a double-laminated structure reminiscent of a nuclear envelope. Although most eggs obtained 11.5 to 12 hours after induced ovulation and in vitro fertilized displayed morphogenetic patterns similar to those described for in vivo fertilized ova, some (10%) contained three pronuclei. Many eggs obtained 13 to 15 hours after induced ovulation and subsequently mixed with sperm in vitro appeared to undergo processes of fertilization typical of in vivo fertilized eggs, however, approximately 30% contained subnuclei in association with the male pronucleus. Few eggs (15%) aged 12 hours prior to in vitro fertilization displayed patterns of pronuclear development and association typical of fertilized unaged ova. Subnuclei developed in many of the fertilized ova. Supernumerary sperm nuclei, which did not develop into male pronuclei, were observed in some zygotes. Cleavage of eggs aged 12 hours prior to fertilization was abnormal or retarded. After 24 hours in culture approximately 16% of the eggs fertilized. Seventy percent of the fertilized eggs failed to support the development of a male or female pronucleus.

Animals↗
PubMed2005

Sustainability of farmers' soil fertility management practices: a case study in the North China Plain.

To ensure regional self-sufficiency and adequate rural livelihoods in the North China Plain (NCP), tremendous efforts were made over the last two decades by the Chinese government to raise the productivity of crops, despite increasing pressure on the land caused by a growing population. Emphasis was placed on high external input use, especially for wheat, maize and cotton, ignoring the particularities and limitations of the natural resource base. This study assesses the sustainability of current soil fertility management practices on the basis of selected location-specific indicators, such as fertilizer use, soil pH, soil organic matter content, levels of nitrogen (N), phosphorus (P) and potassium (K) in the soil, and identifies determining factors of the yield and environmental impacts of inputs use. Data used for the analysis were gathered from soil tests, groundwater and chive plant tests, household surveys, and statistical yearbooks. Stepwise multiple regression analysis is applied to determine factors affecting the yields. The study revealed unbalanced use of nutrients. Organic fertilizers (manure, crop residues) and K are insufficiently applied, whereas N and P are considerably overused in comparison with recommended doses. The intensive cropping in the area using high-input technologies -particularly fertilizer- has resulted in a remarkable general enhancement of crop productivity and improvement of soil fertility over the years. The yield of wheat and maize has increased 173 and 180 kg ha(-1) annually from 1982 to 2000, respectively and soil fertility status also improved over the years and the values of the selected indicators are within the borderline for sustainability. Irrigation water, FYM application, and total labor used during the cultivation season (with the exception of cotton and chive) for production are the main factors determining the yields of four major crops under study, while popularly and overly used N did not appear to be a significant factor affecting the yield. Its overuse, however, leads to leaching of nitrate into groundwater and nitrate enrichment of vegetables. Of 20 groundwater samples, 16 showed nitrate levels between 55 and 180 mg l(-1), which exceeds recommendations for drinking water (<or=50 mg l(-1)), and 19 out of 20 chive plant samples had nitrate levels more than double the maximum permissible level of 700 mg kg(-1) which causes contamination of groundwater and vegetables. If the current methods of soil fertility management are continued, groundwater and food contamination will increase and jeopardize the sustainability of the current land use systems. Present soil fertility management practices at the farm level are not sustainable. However, there are possibilities to improve farmers' soil fertility management practices, for instance, it is necessary to recommend soil and/or plant testing to adjust fertilizer and/or manure application rates to crops to reduce excessive nutrient input, and to adopt appropriate decision support systems for efficient and sustainable management of production resources.

Agriculture↗
PubMed1983

Correlation of human in vitro fertilization with the hamster egg bioassay.

We compared fertility potential measurements by the zona-free hamster egg bioassay with the in vitro fertilization of human eggs. Sperm from 24 husbands participating in an in vitro fertilization-embryo transfer program were used in 27 inseminations of the wives' eggs and in simultaneous inseminations of hamster eggs. In seven cases, a positive fertility assessment was obtained in the absence of fertilization of the wives' eggs attributable to egg immaturity or in one case to equipment failure. In the remaining 20 cases, at least one egg was fertilized, for a level of 73%. In 90% of the husbands who fertilized their wives' eggs, a positive fertility assessment was obtained. Two husbands gave false-negative assessments. To account for these, alternative culture conditions were examined; sperm exposure to longer preincubations or at higher concentrations usually improved assessments. These results indicate that fertility assessment with this bioassay is highly correlated with the fertilization of human eggs in vitro.

Animals↗
PubMed1990

Zona drilling enhances fertilization by mouse caput epididymal sperm.

Spermatozoa from the caput epididymis are known to be much less capable of fertilization when compared to sperm from more distal segments of the epididymis. The purpose of this study was to determine if two micromanipulative techniques, zona drilling (ZD) and a modification of partial zona dissection (PZD), could be used to enhance fertilization with caput epididymal sperm. A mouse in vitro fertilization model was used. Inseminating oocytes with 500-1,000 sperm/oocyte from the cauda epididymis as a control resulted in fertilization of 98 of 300 (32.6%) oocytes. Of those fertilized, 47 developed to the blastocyst stage (47.9%). Caput sperm fertilized 13 of 116 (11.2%) nonmanipulated oocytes. Only 1 of 13 developed into a blastocyst, while with oocyte ZD, caput sperm fertilized 24 of 144 (16.7%) oocytes, 50% of those fertilized developing to blastocyst (P = 0.0129). When modified PZD was performed on oocytes, only one of 23 was fertilized, with no blastocyst development. These results indicate that acid Tyrode ZD enhances both fertilization and early embryonal development when caput epididymal sperm are used for insemination. These mouse studies suggest that ZD or other micromanipulation techniques may prove clinically useful in men with proximal epididymal obstruction where only caput sperm are available.

Animals↗
PubMed1987

Dilauroylphosphatidylcholine liposome effects on the acrosome reaction and in vitro penetration of zona-free hamster eggs by bull sperm: II. A fertility assay for frozen-thawed semen.

Frozen-thawed sperm from five bulls with fertility rates ranging from 48% to 77% were treated with seven concentrations of dilauroylphosphatidylcholine (PC12) liposomes to induce an acrosome reaction (AR) that enabled sperm to penetrate eggs. Treated sperm were incubated with liposomes for 7 min prior to insemination of zona-free hamster eggs in vitro. Sperm and eggs were incubated 3 hr at 39 degrees C prior to fixation, staining, and examination for sperm penetration and nuclear decondensation. The percentage of motile sperm immediately after thawing as well as after treatment with liposomes had a low correlation with sire fertility (r = .39 and less than or equal to .63, respectively). The percentage of sperm exhibiting an AR was more highly correlated with fertility (r less than or equal to -.85). Similar correlations were found between fertility and the penetration rates of zona-free hamster eggs or the total number of penetrating sperm. When data for two high and for two lower fertility bulls were each grouped to increase information per data point the correlation between the PC12 concentration giving the maximum proportion of eggs penetrated and fertility was r = .92 (P less than .05). The correlation between the PC12 concentration producing the most total sperm penetrating the eggs and fertility r = .97 (P less than .05). It was concluded that PC12 liposomes induced an AR in bull sperm frozen-thawed in egg yolk extender. Frozen-thawed sperm from low fertility bulls require less PC12 to induce the AR and to penetrate zona-free hamster eggs than do sperm from higher fertility bulls. These differences in lipid requirements may help to provide a quick, direct laboratory assay method to estimate the fertility of frozen bull semen.

Acrosome↗
PubMed2004

Fertility of long-term male survivors of acute lymphoblastic leukemia diagnosed during childhood.

Fertility impairments among men treated during childhood for cancer are known to occur after some, but not all, types of anti-cancer therapy. This is the first study to evaluate proven fertility among adult male survivors of childhood acute lymphoblastic leukemia (ALL). In a retrospective cohort study, proven fertility (ever fathered a pregnancy) was evaluated by self-report among 213 men treated for ALL before age 18 on protocols of the Children's Cancer Group (CCG). Controls (N = 145) were drawn from among male siblings. Overall, with a proportional hazards analysis, proven fertility of male survivors was not different from that of controls (relative fertility (RF) = 0.95, 95% CI 0.63-1.43). However, married men treated before age 10 with high dose (24 cGy) cranial radiotherapy (RT), without spinal RT, had only 9% of the fertility of controls (Relative risk, RR = 0.09, 95% CI 0.01-0.82). High dose cranial RT at older ages was not associated with a statistically significant fertility deficit (RR = 0.56, 95% CI 0.25-1.28). In this first study of proven fertility among men treated for childhood leukemia, the majority of survivors showed no evidence of fertility impairment compared to controls. However, men treated at a young age with high dose cranial RT may have impaired fertility. These results suggest that further investigation of men with these treatments is needed to confirm and extend these findings.

Adolescent↗
PubMed1995

A protein of the sea urchin cortical granules is targeted to the fertilization envelope and contains an LDL-receptor-like motif.

Cortical granules of eggs contain a population of heterogeneous proteins that are sequestered selectively within the cortical granule during oogenesis and that participate in the block to polyspermy during the fertilization reaction. To begin to understand the targeting mechanism of proteins to this organelle, we have identified cDNA clones that encode proteins of the cortical granule. Here we characterize the protein encoded by the cDNA, SFE 9, which is packaged specifically into the spiral lamellae of the cortical granules in the sea urchin Strongylocentrotus purpuratus. The SFE 9 protein showed a molecular mobility in PAGE of 150 kDa, close to the estimated 128 kDa predicted by cDNA sequence, and contained three regions of distinct repeating sequence. Each type of repeat sequence was of different length, frequency, and amino acid composition, but each type showed a high degree of conservation within a repeat type. A fourth region of sequence showed similarity to the low-density lipoprotein (LDL)-receptor motif. The N-terminal 2/3 of the protein contained an abundance of cysteine residues with regular and conserved spacings. Upon fertilization, SFE 9 was secreted and was rapidly incorporated into the fertilization envelope. The integration of SFE 9 into the fertilization envelope was complete within 5 min post-fertilization and was mediated by ovoperoxidase-catalyzed cross-linking. Incorporation of SFE 9 into the fertilization envelope was not uniform. Instead, it concentrated to the microvillar casts both in normal and in ovoperoxidase-inhibited fertilization envelopes. Thus, SFE 9 shows molecular heterogeneity within the fertilization envelope and the targeted integration is independent of ovoperoxidase activity. The strong repeat regions and the LDL-receptor motif of SFE 9 are postulated to be used in specific protein-protein interactions that occur either during traflicking to the cortical granules during biogenesis or to the fertilization envelope during the fertilization reaction.

Amino Acid Sequence↗
PubMed2000

The alphaBbetaC integrin is expressed on the surface of the sea urchin egg and removed at fertilization.

Integrins are expressed on the surface of some vertebrate eggs where they are thought to have a role in fertilization. The objective of this study is to determine if integrins are expressed on sea urchin eggs. The alphaB and betaC subunits were cloned using the homology polymerase chain reaction. Monoclonal and polyclonal antibodies were developed against bacterially expressed fragments of the extracellular domains of the betaC subunit and the alphaB subunit. As well, a monoclonal antibody was developed against a synthesized peptide corresponding to part of the cytoplasmic domain of betaC. Analysis of biotinylated egg cortex extracts immunoprecipitated with either anti-betaC or anti-alphaB yields bands of 130 and 225 kDa. Immunoblots confirm that betaC is part of the complex immunoprecipitated with anti-alphaB. Confocal immunofluorescence and immunogold electron microscopy show that betaC is present on the surface of the unfertilized egg at the tips of microvilli and in cortical granules. During the cortical reaction, immunoreactivity with antibodies to the extracellular domains of betaC and alphaB disappears from the egg surface, and microvillar casts on the fertilization envelope become immunoreactive. With antibodies to the cytoplasmic domain of betaC, immunoreactivity is lost from the surface of the egg, but the fertilization envelope does not immediately become immunoreactive. In immunoblots of egg cortex there are immunoreactive bands of the predicted sizes for alphaB and betaC. However, in fertilization envelopes, a second band that is slightly lower in molecular weight is also present. Eggs fertilized in the presence of soybean trypsin inhibitor have elongated microvilli that remain bound to the elevating fertilization envelope and immunoreactive to anti-betaC antibodies. Eggs fertilized in the presence of an ovoperoxidase inhibitor, 3-amino-1,2,4-triazole, have a patchy distribution of betaC immunoreactivity in fertilization envelopes. Together, these data suggest that alphaBbetaC integrins are expressed on the surface of unfertilized eggs and, during the cortical reaction, the extracellular domains are cleaved by proteases and cross-linked into the fertilization envelope by ovoperoxidase. The alphaBbetaC integrin receptors may have several potential functions prior to their removal at fertilization, including attachment of the vitelline envelope to the egg surface and anchoring the cortical cytoskeleton.

Amino Acid Sequence↗
PubMed2003

Disordered zona pellucida-induced acrosome reaction and failure of in vitro fertilization in patients with unexplained infertility.

OBJECTIVE: To determine the relationship between the zona pellucida (ZP)-induced acrosome reaction (AR) and fertilization rate and pregnancy rate in standard IVF and the frequency of disordered ZP-induced AR (DZPIAR) in patients with unexplained infertility. DESIGN: Prospective study. SETTING: Academic research and teaching tertiary hospital. PATIENTS: Patients with unexplained infertility with normal semen analysis. INTERVENTION: None. MAIN OUTCOME MEASURE: Semen analysis, the ZP-induced AR, and measurements of fertilization rate and pregnancy rate with in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). RESULT(S): A statistically significant correlation was found for the ZP-induced AR and fertilization rate with standard IVF (n = 65). Patients with DZPIAR (ZP-induced AR of 16%, who had an average fertilization rate of 61%. The sensitivity and specificity of DZPIAR for prediction of IVF rates <30% and >or=30% were 80% and 86%, respectively. Of 260 patients screened, the frequency of DZPIAR was 29%. Ten patients with DZPIAR had an average fertilization rate of 15% and no pregnancy with initial IVF cycles, and a fertilization rate of 61% (with three live-birth pregnancies) with subsequent ICSI cycles. Another 33 patients with DZPIAR were treated with ICSI alone, with an average fertilization rate of 71% and a live-birth pregnancy rate of 17% per embryo transfer. Sixteen of the patients had live-birth pregnancies (including one set of twins) after undergoing an average of 3.2 embryo transfers. CONCLUSION(S): Patients with DZPIAR have a low or zero fertilization rate with standard IVF but high fertilization and pregnancy rates with ICSI. Up to 29% of patients with unexplained infertility with normal semen analysis may have this condition, which should be diagnosed and treated with ICSI rather then standard IVF.

Acrosome Reaction↗
PubMed1984

Fertilization of human oocytes following reinsemination in vitro.

The reinsemination of human oocytes that failed to show any evidence of fertilization 12 to 14 hours after insemination was examined to determine whether this would increase success of in vitro fertilization or be of use in determining the fertilizing capacity of the husband's spermatozoa. Reinsemination with spermatozoa of a donor of known fertility resulted in a significantly higher fertilization rate than reinsemination with the husband's spermatozoa. However, the rate of the spontaneously delayed fertilization in oocytes that were not reinseminated was not significantly different from fertilization rates following reinsemination with either the donor's or the husband's spermatozoa. One pregnancy that miscarried at 12 weeks' gestation was obtained from reinseminated oocytes, and none was obtained from oocytes that were spontaneously delayed in fertilization. It is concluded that at present neither reinsemination nor embryo replacement in utero of embryos resulting from delayed fertilization is useful for human in vitro fertilization.

Culture Media↗
PubMed1992

A prospective controlled evaluation of TEST-yolk buffer in the preparation of sperm for human in vitro fertilization in suspected cases of male infertility.

OBJECTIVE: To evaluate sperm preincubation in tes and tris (TEST)-yolk buffer as a potential enhancing agent of fertilizing capacity of sperm during human in vitro fertilization (IVF). DESIGN: Oocytes obtained during IVF were divided into two groups: one group fertilized with TEST-yolk buffer-treated sperm and the other group with standard-prepared sperm. SETTING: The University of Southern California IVF Program. PATIENTS: Thirty-nine couples with suspected male factor infertility undergoing IVF. INTERVENTIONS: Preinsemination incubation of sperm in TEST-yolk buffer for 24 hours. MAIN OUTCOME MEASURES: Fertilization rates in vitro. RESULTS: TEST-yolk buffer-treated sperm fertilized 140 of 241 oocytes (58%), whereas control sperm fertilized 108 of 251 oocytes (43%). Of four couples who had previously failed to fertilize during IVF, one fertilized with both specimens and three fertilized with TEST-yolk buffer-treated sperm only. CONCLUSIONS: TEST-yolk buffer pretreatment of sperm for 24 hours results in higher fertilization rates during IVF among suspected male factor patients.

Egg Yolk↗
PubMed1993

Localization of antibodies on spermatozoa and sperm movement characteristics are good predictors of in vitro fertilization success in cases of male autoimmune infertility.

OBJECTIVE: To define sperm factors related to in vitro fertilization (IVF) failure in cases of antisperm autoimmunity. DESIGN: A detailed analysis of sperm morphology, movement characteristics, acrosomal function, and antibody binding was performed on the sperm population selected on a discontinuous two-layer Percoll gradient and used for IVF. The results were compared retrospectively between fertilizing (n = 13) and nonfertilizing (n = 11) sperm populations. PATIENTS: Twenty-one infertile couples undergoing 24 cycles of IVF treatment because of antisperm autoimmunity were included in this study. RESULTS: Fertilizing and nonfertilizing sperm populations were not different with respect to the percentage of motility, the normal morphology, the multiple anomalies index, the acrosome abnormalities, and the spontaneous or induced acrosome reaction. If the proportion of spermatozoa coated with either immunoglobulin (Ig)A or IgG antibodies was similar in the two groups, their localization was often different: antibodies were mainly on the sperm heads in the cases of fertilization failure. There were significant differences between fertilizing and nonfertilizing sperm samples in several movement parameters. Among them, the amplitude of lateral head displacement (ALH) was the most significantly correlated with fertilization success. Finally, spermatozoa were poorly bound to the zona pellucida (ZP) when fertilization failed, whereas high numbers of spermatozoa were attached to the ZP when fertilization occurred. CONCLUSION: Fertilization failure in patients with antisperm antibodies may be the result of several factors in which the impact of the antibodies on the membrane function play a critical role. Movement parameters, particularly the ALH and the localization of antibodies on migrated spermatozoa could predict the IVF failure or success more accurately than the proportion of antibody-coated spermatozoa in the inseminated populations. The fertilization failure was associated with an incapacity of spermatozoa to bind to ZP.

Acrosome↗