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At least 19 recordsLinked to original sources

PubMed1992

Increased fertilization and pregnancy rate in polypronuclear fertilization cycles in in vitro fertilization-embryo transfer.

OBJECTIVE: To compare fertilization and pregnancy rates between cycles with polypronuclear fertilizations and cycles with normal fertilizations. DESIGN: In vitro fertilization-embryo transfer (IVF-ET) cycles in which oocytes were retrieved were divided into two groups according to the nature of fertilization. PATIENTS: All patients were participants of our IVF-ET program. RESULTS: A significantly higher fertilization rate was found in the polypronuclear fertilization cycles (61% versus 36.6%) and also an improved pregnancy rate (47.5% versus 19.6%) and per embryo transfers (53% versus 28.8%). The vast majority of polypronuclear fertilizations occurred in mature oocytes. CONCLUSION: We believe that the increased receptability of the oocytes improves fertilization and conception rates. The polypronuclear fertilization is an extreme expression of such improved receptibility and should be considered as an encouraging sign for conception.

Embryo Transfer↗

PubMed1992

Sperm creatine phosphokinase M-isoform ratios and fertilizing potential of men: a blinded study of 84 couples treated with in vitro fertilization.

OBJECTIVE: To examine the value of sperm creatine phosphokinase M-isoform (CK-MM) measurements toward predicting fertilizing potential of men. DESIGN: In 84 in vitro fertilization (IVF) couples without knowing the semen parameters, reproductive history or the outcome of the IVF cycles, we determined the sperm CK-MM ratios (the proportion of sperm CK-MM versus CK-MM+CK-BB). Husbands with less than 10% or greater than or equal to 10% CK-MM ratios were classified as "low likelihood for fertilization" (CKMM-Infertile, n = 22) or "high likelihood for fertilization" (CKMM-Fertile, n = 62), respectively. RESULTS: Both the CKMM-Infertile and CKMM-Fertile groups (CK-MM ratios: 4.9% +/- 0.6% versus 31.1% +/- 1.8%) were in the normospermic range (31.5 +/- 6.9 versus 78.4 +/- 5.9 x 10(6) sperm/mL and 45.6% +/- 5.0% versus 54.0% +/- 2.0% motility). The fertilization rates (6.2 versus 4.9 oocytes inseminated) were 14.2% versus 53.4%, and 72.7% versus 25.8% of the couples failed to achieve any oocyte fertilization. All 14 pregnancies (16.7% rate) occurred in the CKMM-Fertile group. The pregnancy rate in the 62 CKMM-Fertile couples was 22.6%, and considering only the 46 CKMM-Fertile women in whom oocyte fertilization occurred, it was 30.4%. Among the 22 CKMM-Infertile men, 9 were normospermic and 9 of the 62 CKMM-Fertile men were oligospermic. Within the CKMM-Fertile group, 12 and 2 of the 14 pregnancies occurred by the 53 normospermic and 9 oligospermic men (22.6% versus 22.2% rate). CONCLUSIONS: Sperm CK-MM ratios, a measure of normal sperm development, predict fertilizing potential independently from sperm concentrations. Sperm CK-MM ratios also detect unexplained male infertility (infertile men with normospermic semen), a diagnosis that until now could not be substantiated.

Biomarkers↗

PubMed1992

Migration sedimentation technique as a predictive test for the fertilizing capacity of spermatozoa in an in-vitro fertilization programme.

The migration-sedimentation technique (MST) has been proposed as a means of separating high quality motile spermatozoa. The present study was conducted in order to evaluate whether sperm performance following separation by MST predicts their fertilizing capacity in an in-vitro fertilization (IVF) programme. Ninety semen specimens were analysed for use in an IVF-embryo transfer (ET) programme. Each specimens was divided into two parts: one was processed in the IVF programme and was used after sperm swim-up separation for insemination of human ova. The other aliquot (0.2 ml) was separated by MST, and the sperm then characterized by their concentration, motility, degree of motility and morphology. Sperm characteristics after separation by MST were then correlated with the results of the IVF-fertilization rates. In 79 of 90 IVF-ET cycles, at least one oocyte was fertilized. All post-MST sperm characteristics were significantly higher in cycles with fertilizations compared to IVF cycles without fertilization. A larger percentage of the total motile spermatozoa were recovered after MST in semen specimens with fertilization, compared to semen specimens without fertilization (39.9 +/- 3.6 and 20.6 +/- 6.6%, respectively; P < 0.05). This value was correlated with the percentage of fertilized oocytes (r = 0.24; P < 0.02). More IVF cycles with fertilizations were recorded in cases in which the recovery of motile sperm was > 25% (P < 0.005), or when more than 1.5 x 10(6) motile spermatozoa were recovered after MST (P < 0.0001). As sperm characteristics after MST correlated significantly with their fertilizing capacity, the MST test could be used in evaluation of the fertilizing capacity of spermatozoa.

Cell Separation↗

PubMed1991

[Comparative study of the morpho-functional features of the sperm of fertile and infertile men and their relation to fertilizing ability].

The recent advances in assisted reproduction procedures have helped to the better understanding of the female reproductive physiology and pathology, however, male infertility remains as a poor explained medical problem, nevertheless it occurs in almost 50% of infertile couples. Oligoasthenozoospermia is one of the more common causes of male infertility, therefore we measured in 10 patients with this diagnosis and in 10 fertile euspermic men, besides the parameters included in the standard semen analysis, the quantitative motility (photography method), capacitation-acrosome reaction and the sperm ability to fertilize zona-free hamster oocytes, with the aim to correlate the morphofunctional characteristics of the male gametes with their fertilizing capacity. The results showed significant differences in every parameter studied, including the correlation analysis. In relation with the in vitro induction of the acrosome reaction in both groups, we found significant correlations of the sperm fertilizing ability and the progressive sperm motility with this parameter (fertile group: RS = 0.834, P less than 0.005 & RS = 0.612, P less than 0.05; infertile group: RS = 0.986, P less than 0.001 & RS = 0.536, P less than 0.05 respectively), nevertheless the sperm rate which completed this process was low in relation to the total sperm population even in the fertile men (9.4 +/- 2.0% & 4.4 +/- 2.5% acrosome reacted cells after 18 h of incubation, in the fertile and infertile males respectively). The results also showed the presence of fully capacitated spermatozoa in both groups, since they penetrated the zona-free hamster eggs and decondensed their chromatin (73.9 +/- 13.4% & 10.4 +/- 7.7% penetrated eggs in the euspermic and oligoasthenozoospermic individuals respectively), however, the spermatozoa from the oligoasthenozoospermic men showed low polyspermy indexes too (0.1 penetrated spermatozoa/inseminated oocyte). In this last group we found, in addition, that the mean sperm velocity and the abnormal sperm morphology rate showed significant correlations with the fertilizing ability of the male gametes too (RS = 0.986, P less than 0.005 & RS = -0.942, P less than 0.005. respectively). These data allow us to suggest that before an infertile man is involved in any assisted reproduction program, the presence of possible morphofunctional alterations in the spermatozoa be analyzed, with the aim to be able to make a better prognosis about the success with these patients.

Acrosome↗

PubMed1979

Infertility in the turkey. III. Effects of sera from sterile and fertile females on the fertilizing ability of spermatozoa.

In an attempt to understand the cause for spontaneous infertility in female turkeys, sera were obtained from a flock suffering this condition. These sera, from hens of known fertility, were tested for anti-fertility actions by incubating semen in them. After incubation, semen was inseminated into unrelated recipient hens. In the first of two experiments, semen incubated in sera from high fertility hens (average 89%) produced a fertility level of 72.7% over an 8 week period while semen incubated in sera from sterile hens significantly reduced fertility to 52.3%. In a second experiment sera from sterile donors again caused a significant reduction in the fertilizing ability of sperm (56.3% for sera from sterile hens vs. 73.5% for sera from high fertility hens). These results indicate the presence of a factor(s) in the sera of sterile hens which may be causally related to their infertility.

Animals↗

PubMed1978

Age, biological factors, and socioeconomic determinants of fertility: a new measure of cumulative fertility for use in the empirical analysis of family size.

To influence the number of children ever born to a woman, socioeconomic variables must operate through behavioral and biological mechanisms such as the age at marriage, the level of fertility in the absence of deliberate fertility control, and the level of control exerted to reduce fertility within marriage. In this paper, we propose a new measure of cumulative fertility which is standardized for the age-fecundity relationship and for exposure to the risk of conception associated with duration of marriage. A simple model of fertility behavior which incorporates some of the mechanisms through which socioeconomic factors may affect fertility is developed and applied to data from the United States to demonstrate the properties of alternative measures of family size. The results indicate that use of the new measure allows more precise estimates of socioeconomic fertility relationships than would be obtained with children ever born or by sample stratification.

Adult↗

PubMed1975

[Fertility and fertility problems in some beef herds in Sweden (author's transl)].

The purpose of the study was to investigate the fertility level, some factors affecting fertility and problems of infertility in selected Swedish beef herds. The investigation included 31 herds, 19 of which had Herefords, 13 Charolais, 2 Aberdeen Angus and 1 Limousins. The total number of mature females was 703, including 147 feifers of breeding age. Most data were collected at personal visits to the herds. The results are presented in Tables I--XV and Figures 1--2. The service period coincided roughly with the grazing period and lasted usually 4--5 months. Seventyfive per cent of the females calved during the period February-May. The fertility levels were comparatively good. The percentage of pregnancy at rectal examination performed at the end of the service period was 89.5; however the average calving percentage was only 87.5. The highest calving percentages were recorded for Aberdeen Angus and crossbreds. Also the calf crop, it is the number of calves born alive and surviving 24 hours per mature female was the highest for these two groups; 0.91 and 0.90 respectively. The mean interval from calving to conception was 80.3 days in Herefords, 83.4 days in Aberdeen Angus, 85.6 days in crossbreds and 92.3 days in Charolais. The percentage of animals pregnant within 90 days after calving was on an average slightly more than 50 per cent. The interval from calving to conception rose gradually when the interval from calving to expoure to bull exceeded 40 days. Mean percentages of still born calves were 5.9 in cows and 13.7 in heifers. As far as the fertility level is concerned there does not seem to be any disadvantage in keeping the bull together with the females during the calving period. However, in this case the next calvings will occur over an extended period of time. If the intention is to concentrate 50 per cent of the calvings within the period of one month then the females should be exposed to the bull from 41--60 days after calving at the earliest. In case the females were exposed to the bull from 41--60 days after calving and onwards, 95 per cent of the females finally pregnant had conceived at the end of a 3 months service period. Under such conditions a bull may be able to serve two groups of females within the same grazing period. Cows calving during July-September had the lowest pregnancy rate and those calving during October-December the highest at the following service period. The incidence of ovarian cysts was very low. About 1/3 of those buls serving at least 10 females each obtained calving percentages less than or equal to 80. Herds recording low calving percentages had to a great extent used young bulls, 12--15 months of age at the beginning of the service period. Only for two groups of females out of eleven which had been served by young bulls calving percentages greater than 80 were noted. A more efficient control of the fertility of the bulls could markedly improve the fertility of some herds.

Abortion, Veterinary↗

PubMed1977

[The decline of fertility in Western Europe. II. Which fertility rate would be desirable in France? (author's transl)].

A way to try and assess the significance of such or such level in long term fertility is to work out population projections based on a variety of assumptions and to compare their different implications. The age pyramids of France until 2100 that derive from four contrasted evolutions of fertility are studied in the present article: completed fertility in birth cohorts ranging from 1.4 to 2.6 children per woman. While some demographic parameters are not much sensitive to the assumption made for the fertility level (e.g. percent of economically active people in total population), others are closely related to fertility (such as total number of inhabitants, percent of younger people or of older people in total population, annual rate of entry into economically active population). In France, where population density is much lower than in most neighbouring countries, a fertility level that would lay at -- or a little higher than -- replacement (i.e. 2.1 children per woman) can be considered as a desirable target.

Adolescent↗

PubMed1991

Assessment of the relevance of zona pellucida antibodies in serum and cervical mucus in patients who have fertilization failure during in vitro fertilization.

OBJECTIVE: To assess whether antibodies to the zona pellucida can cause fertilization failure during in vitro fertilization (IVF). DESIGN: Two methods for detecting zona pellucida antibodies were used to assess 20 women undergoing IVF. Nine patients had failed fertilization during the treatment cycle. SETTING: Academic IVF department of a teaching hospital. PATIENTS: Infertile patients previously assessed as requiring IVF. INTERVENTIONS: Gonadotropin-releasing hormone analogue to achieve pituitary down regulation and human menopausal gonadotropin for superovulation. Transvaginal ultrasound directed oocyte recovery. Cervical mucus and serum samples were obtained. MAIN OUTCOME MEASURES: The presence of antizona pellucida antibodies in serum or cervical mucus in relation to fertilization. RESULTS: Seven of 20 patients had antizona antibodies in serum and 7 of 20 patients had antibodies in mucus. Only 1 patient had antibodies in both samples. No correlation between the presence of antibodies in either sample and failure of fertilization was found. CONCLUSION: Detection of antizona pellucida antibodies by the methods described have no role in the prediction of IVF.

Antibodies↗

PubMed1992

Improved fertilization rate in an in vitro fertilization program by egg yolk-treated sperm.

High fertilization and PRs have been achieved by using thawed donor sperm cryopreserved with medium containing EY. The aim of our study was to examine the possible effect of EY on the fertilizing capacity of fresh sperm in an IVF program. Preincubation of spermatozoa in EY for 2 hours at room temperature significantly improved fertilization (P less than 0.001) in couples who had low fertilization rates in previous cycles, whereas no effect was found concerning couples with high fertilization rates.

Egg Proteins↗

PubMed1977

[The decline of fertility in Western Europe. III. Some considerations on future evolution and on policy measures aiming at supporting fertility (author's transl)].

The analysis of recent fertility trends in France lead to hold as plausible that women born after 1950 will not reach replacement level. On the other hand, the period total fertility rate, which has not fallen as low as those observed in some neighbouring countries, might well continue to decline and thus disturb the alimentation of age-pyramid, despite its slower decrease in the course of 1976. Considering present fertility situation in France, an action of the State appears to be desirable. The factors which condition fertility fall largely out of the range of well-established knowledge. Though, it seems that they are deeply rooted in collective consciousness and that the possibilities they leave to voluntary action on fertility trends is relatively modest. Moreover, to be efficient, the means used must be important. The lines of possible action seem, in our view, to relate to two main fields: research of a better conciliation of professional activity and motherhood, increase of family benefits for second but specially for third and following children.

Birth Rate↗

PubMed1975

In vitro fertilization of rat and mouse eggs by ejaculated sperm and the effect of energy sources on in vitro fertilization of rat eggs.

In vitro fertilization of rat and mouse eggs by ejaculated or epididymal spermatozoa in chemically defined media was studied. Penetration rates by ejaculated sperm was very low (0 to 8%) in the rat, but 11 to 41% of eggs were penetrated by ejaculated sperm in the mouse. The optimal concentration of sperm for in vitro fertilization appears to be similar whether ejaculated or epididymal sperm were used. The time of sperm penetration in the mouse eggs, however, was delayed for one-half to one hour when ejaculated sperm were used. The importance of sodium pyruvate, sodium lactate and glucose in the medium containing bovine serum albumin for in vitro fertilization of rat eggs was examined. When rat eggs in cumulus clot were exposed to epididymal sperm preincubated for five hours, the presence of sodium pyruvate, sodium lactate and glucose was found to play an important role. When exposed to non-incubated epididymal sperm sodium pyruvate could be omitted without much decline of the fertilization rate. When the denuded eggs were exposed to non-incubated sperm, penetration rates were very low (0 and 5%) in the absence of pyruvate. It appears that although lactate, pyruvate and glucose are all important for in vitro fertilization of rat eggs, pyruvate can be supplied by the follicular cells surrounding the eggs.

Animals↗

PubMed1992

Is fertility-problem stress different? The dynamics of stress in fertile and infertile couples.

OBJECTIVE: To compare the dynamics of fertility-problem stress experienced by wives and husbands in infertile couples with the dynamics of stress from other sources experienced by members of couples presumed to be fertile. DESIGN: Relationships of stress to four marriage factors and four aspects of life quality (subjective well-being) are examined within a causal modeling framework using data from structured interviews. SETTING: Face-to-face interviews were conducted in study participants' homes. PARTICIPANTS: Wives and husbands from 157 couples with primary infertility and from 82 presumed-fertile couples were studied. MAIN OUTCOME MEASURES: Final outcome measures were four multi-item scales assessing life quality with regard to the marriage, own self-efficacy, own health and appearance, and life as a whole. Intervening outcome scales measured four marriage factors: marital conflict, sexual self-esteem, sexual dissatisfaction, and frequency of intercourse. RESULTS AND CONCLUSIONS: Higher levels of stress, regardless of whether that stress was from attempting to solve a fertility problem or another problem, were related to reduced marital functioning and decreased life quality. For husbands, the strengths of the linkages did not depend on the source of the stress. For wives, however, the causal model suggested that fertility-problem stress had stronger negative impacts on sense of sexual identity and self-efficacy than did stress from other problems (P less than 0.05). Stress from any source had more impact on the lives of wives than of husbands, more impact on satisfaction with self and general well-being than on satisfaction with the marriage or health, and affected life quality mostly indirectly through its impacts on the marriage factors.

Adult↗

PubMed1992

Subnormal sperm parameters in conventional semen analysis are associated with discrepancies between fertilization and pregnancy rates in in-vitro fertilization and embryo transfer.

Three hundred and twenty-eight consecutive treatment cycles in 168 couples were analysed retrospectively in order to examine the influence of conventional semen analysis results on the outcome of in-vitro fertilization and embryo transfer with respect to the occurrence of both fertilizations and pregnancies. All treatments were performed under maximally standardized and controlled conditions. Each of the three main determinants of the spermiogram, namely the concentration, motility and morphology of sperm in seminal plasma, was of significant importance for fertilization and subsequent pregnancy. Best correlations were achieved by counting the number of progressively (a+b) motile sperm and the number of normally formed sperm in seminal plasma. The pregnancy rate was reduced significantly in cases in which the sperm concentration was < 10 x 10(6) ml-1 (P < 0.01), or in which there was < 40% progressively motile sperm (P < 0.001), or < 30% normally formed sperm (P < 0.001). If more than one parameter in the spermiogram was abnormal, the fertilization rate depended mainly on the most disturbed sperm parameter. The implantation rate as well as the pregnancy rate was reduced significantly in patients with low progressive sperm motility and normal morphology rates. The difference could only be attributed partially to the lower number of embryos replaced. In conclusion, subnormal sperm quality seems to interfere with developmental stages beyond the process of fertilization.

Adult↗

PubMed1991

Analysis of poultry fertility data. 2. Comparison of long- and short-term fertility trials.

The purpose of the present study was to determine the effect of egg collection interval on interpretation of fertility trial results. Low-fertility (LF) and randombred (RB) Delaware hens were inseminated with spermatozoa from LF or RB Delaware roosters. Three replicate trials were performed for each cross. Eggs were collected for 21 days following insemination. Fertility was analyzed with a log odds model following logit transformation. Separate analyses were performed on data collected throughout the first 7 days and the entire egg collection interval. Duration of fertility over the 21-day interval was analyzed by iterative least squares. Whereas the 21-day egg collection interval afforded detection of differences between males and between females, no differences were observed following analysis of data from the 7-day interval. Differences in reproductive efficiency also were detected when data were analyzed by iterative least squares. Thus, the value of a fertility trial is, in part, determined by the length of the egg collection interval.

Animals↗

PubMed1991

Cannabinoids inhibit fertilization in sea urchins by reducing the fertilizing capacity of sperm.

Delta-9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN) inhibit fertilization in the sea urchin Strongylocentrotus purpuratus by reducing the fertilizing capacity of the sperm. Sperm fertility depends upon their motility, and their capacity to undergo the acrosome reaction upon encountering a specific ligand derived from the egg's jelly coat. The acrosome reaction involves exocytosis of the acrosomal granule at the apex of the sperm head and elongation of the acrosomal filament. This process exposes the sperm membrane that will attach to and fuse with the egg. Pretreatment of sperm with THC prevents the triggering of the acrosome reaction by solubilized egg jelly in a dose and time dependent manner. Motility of THC-treated sperm is not reduced compared to control sperm in sea water or vehicle dissolved in sea water. The adverse effects of THC on the acrosome reaction and sperm-fertilizing capacity are reversible. Studies with ionophores suggest that THC blocks the acrosome reaction by affecting event(s) in the stimulation-secretion coupling mechanism in the sperm preceding the opening of ion channels. Ultrastructural studies show that THC, CBD and CBN block the membrane fusion reaction between the sperm's plasma membrane and the acrosomal membrane that normally is elicited in response to stimulation by egg jelly to initiate the acrosome reaction. However, lipid deposits are found in the subacrosomal and centriolar fossae of cannabinoid treated sperm. The nuclear envelope is fragmented in close proximity to the lipid deposits within the subacrosomal fossa. These morphological observations suggest that cannabinoids may activate phospholipase(s) within the sperm. Biochemical studies show that THC activates phospholipase A2 activity in sperm homogenates.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrosome↗

PubMed1992

Teenage pregnancy and fertility in New South Wales: an examination of fertility trends, abortion and birth outcomes.

This paper reviews the data available in New South Wales on teenage fertility rates and pregnancy outcomes. Teenage births comprise six per cent of all births in New South Wales, but they constitute a significant public health problem because they are associated with elevated rates of adverse pregnancy outcomes, which include low birthweight, perinatal death and pre-eclampsia. Risk is concentrated in females under 18 years of age. Pregnancy outcomes for females aged 18 to 19 years are similar to those of women aged 20 to 24 years. Teenage fertility rates have remained stable since the mid-1980s, following a decline which began in the early 1970s. There are large geographic variations in teenage fertility within the state, with the highest rates in the far west of New South Wales and in western Sydney. Teenage pregnancy in New South Wales (as distinct from fertility which reflects births) cannot be assessed accurately because of the lack of information on terminations of pregnancy. However, available data suggest that teenage pregnancy rates have not increased during the 1980s.

Abortion, Induced↗

PubMed1991

The ultrastructure of human cumulus-corona cells at the time of fertilization and early embryogenesis. A scanning and transmission electron microscopic study in an in vitro fertilization program.

We observed the ultrastructure of the cumulus-corona cells (CC cells) surrounding: 1) human preovulatory oocytes unfertilized after in vitro insemination and 2) in vitro-fertilized polypronuclear ova (PO) at the pronuclear stage (3 pronuclei) and during early cleavage, at the 3-8 cell stage (cleaving PO). All the samples were obtained from women who underwent pharmacological hormonal stimulation during in vitro-fertilization procedures. Both cell groups were composed of irregularly rounded CC cells, showing an oval nucleus with one or more reticular nucleoli. Spermatozoa in close contact with CC cells were also seen. Linear and annular gap junctions between neighbouring cells were present, particularly in Group 1. Lipid droplets were present in both groups, appearing slightly more numerous and electron-dense in Group 2. In Group 1, mitochondria were numerous, polymorphic, and provided with cristae varying from lamellar to tubular. In Group 2, mitochondria also showed polymorphism, with bacilliform organelles with tubular cristae being predominant. In both groups cisternae and associated vacuoles and vesicles belonging to the Golgi complex were scattered in the cytoplasm of CC cells. Similarly, tubular and vesicular profiles of smooth endoplasmic reticulum were abundant and uniformly distributed throughout the cytoplasm of CC cells of both groups. In contrast, the abundant rough endoplasmic reticulum in Group 1 was formed by parallel stacks of flattened cisternae, whereas it was less plentiful and not arranged in stacks in Group 2. The CC-cell surface appeared covered by numerous membrane expansions in both groups. The expansions in Group 1 were mainly composed of blebs of various sizes and a few short microvilli, whereas in Group 2 numerous microvilli covered the cell surface. These observations demonstrate that a gradual establishment and maintainance of a steroidosynthetic capability (luteinization) takes place in CC cells, particularly during and shortly after fertilization, as occurs contemporaneously in the granulosa cells of the postovulatory follicle. Our results may be considered as ultrastructural confirmation of the capability of the CC cells to produce small amounts of steroids (estrogens and mainly progesterone). These hormones, alone or together with other substances (proteins, nutrients, growth factors?), might--around the fertilization time--act positively upon the early embryo itself, as well as on the microenvironment in which the embryo develops, both in vivo and in vitro conditions.

Cell Membrane↗