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de Graaff Aisha A - - 2011
To investigate the effect of the nationwide age shift toward later conception on the corresponding subfertile population. Observational study. General population, the Netherlands. Subfertile population, Maastricht University Medical Centre. Women delivering their first child, women entering fertility care. Between 1985 and 2008 the age of women at their first visit ...
Hallén Magnus - - 2011
Several animal studies have raised concern about the risk for obstructive azoospermia owing to vasal fibrosis caused by the use of alloplastic mesh prosthesis in inguinal hernia repair. The aim of this study was to determine the prevalence of male infertility after bilateral mesh repair. In a prospective study, a ...
Colin Alinne - - 2010
To evaluate the impact of age on the expression of apoptotic biomarkers in human spermatozoa. Cross sectional, prospective study. Academic centers. Healthy volunteers with proven fertility, stratified by age (n = 25, range: 20-68 years). Examination of serum hormone levels and basic semen parameters, and assessment of early (plasma membrane ...
Hammiche F - - 2011
Because of changes in the society, couples in Western countries are increasingly delaying reproduction. This is accompanied by unhealthy lifestyles that may be detrimental not only to general health but also to reproductive capacity. It is well known that maternal age has detrimental effects on fertility; the paternal influence on ...
Long J A - - 2010
The fertility rates of cryopreserved poultry semen are highly variable and not reliable for use in preservation of commercial genetic stocks. Our objective was to evaluate the cryosurvival of semen from 8 pedigreed layer lines at 2 different ages: the onset and end of commercial production. Semen from 160 roosters ...
Das Farida Ahmed - - 2010
Selection potential based on differential fertility and mortality has been computed for seven population groups inhabiting different geographical locations of Northeast India. Crow's as well as Johnston and Kensinger's index have been used for the present purpose. Irrespective of the methodology, the total index of selection was found to be ...
Weir Laura K - - 2010
Sperm limitation is widespread across many animal species. Several mechanisms of sperm allocation have been proposed, including optimal allocation according to clutch size and equal allocation across females. However, considerably less effort has been directed at investigating the behavioural signals associated with sperm limitation in males, which may include mating ...
Manier Mollie K - - 2010
Our understanding of postcopulatory sexual selection has been constrained by an inability to discriminate competing sperm of different males, coupled with challenges of directly observing live sperm inside the female reproductive tract. Real-time and spatiotemporal analyses of sperm movement, storage, and use within female Drosophila melanogaster inseminated by two transgenic ...
Hvidtfeldt Ulla A - - 2010
AIMS: The most commonly used indicator of fertility, the period total fertility rate (TFR(p)), tends to underestimate actual fertility when women delay childbearing. The objective of this study was to examine to which extent fluctuations in Danish fertility rates result from changes in timing of births and, thus, whether the ...
Suquet M - - 2010
Changes in sperm features during the movement phase are especially interesting to study in external fertilization species whose sperm duration movement is long because this implies a significant adaptation of moving cells to the external medium. This study describes the changes in tetraploid Pacific oyster sperm characteristics in relation to ...
Peippo J - - 2010
We studied whether bovine embryos developing after in vitro fertilization (IVF) with sex-sorted spermatozoa differed in developmental kinetics, quality and sex ratio from embryos produced with unsorted spermatozoa. Abattoir-derived oocytes were fertilized with X-sorted, Y-sorted or unsorted spermatozoa from a single bull. To evaluate economical use of the sex-sorted spermatozoa, ...
Larson J E - - 2010
This study tested the hypothesis that four inseminations of commercially frozen sexed semen (>or=2.1x10(6) sperm per 0.25-mL straw) in superstimulated embryo donors would yield a percentage and quantity of transferable embryos similar to that achieved with conventional frozen semen. Bos taurus, angus cows (n=32), stratified by age and body condition, ...
Vivas-Acevedo Giovanny - - 2010
To evaluate the effect of presence, grade and anatomical side of varicocele on semen parameters and to identify age-related modifications in semen quality in men with varicocele. A prospective clinical study was performed in 363 men with varicocele and 155 normozoospermic men without varicocele. We determined the presence, grade and ...
Xu Jin - - 2010
The determination of paternity of offspring produced by polyandrous females is essential for the understanding of sperm competition mechanisms. The sterile male technique using radiation is one of the most commonly employed methods for this purpose. However, sterilization using radiation is likely to be restricted by the equipment availability and ...
Wilson Ben - - 2010
The stability of couple partnerships is of continual interest to policy makers and many users of official statistics. This research used a sample of adults (from the Office for National Statistics Longitudinal Study) who were in a partnership (married or cohabiting) in the 1991 Census of England and Wales, and ...
Katz Karin - - 2010
This study investigated a potential independent association between hypovitaminosis D and suspected nonalcoholic fatty liver disease (NAFLD) in a nationally representative sample of the US adolescents. Data from 1630 subjects 12-19 years of age were examined using the National Health and Nutrition Examination Survey, 2001-2004. The vitamin D status of subjects ...
Akter Shamima - - 2010
Early cessation of breastfeeding is a cause of significant concern in many developing countries. Premature discontinuation of breastfeeding is known to be associated with avoidable childhood morbidity and mortality as well as high levels of parity and avoidable pregnancies. Using a publicly available demographic dataset from Bangladesh, we applied a ...
Ga??n Natalia - - 2010
The Iberian lynx (Lynx pardinus) is the most endangered felid in the world. Adequate genetic management of in situ and ex situ populations, and linkage between both, require knowledge on male reproductive biology and factors influencing it. We examined the influence of age, free-ranging versus captive conditions and seasonality on ...
Koskas Martin - - 2010
Objective. To study incidence of abnormal hysteroscopic findings according to age. Methods. We retrospectively studied 557 consecutive office hysteroscopies in patients referred for incapacity to conceive lasting at least 1 year or prior to in vitro fertilization. Rates of abnormal findings were reviewed according to age. Results. In 219 cases, ...
Ally Dilara - - 2010
From bacteria to multicellular animals, most organisms exhibit declines in survivorship or reproductive performance with increasing age ("senescence"). Evidence for senescence in clonal plants, however, is scant. During asexual growth, we expect that somatic mutations, which negatively impact sexual fitness, should accumulate and contribute to senescence, especially among long-lived clonal ...
Charlton Benjamin D - - 2010
Although female mammal vocal behaviour is known to advertise fertility, to date, no non-human mammal study has shown that the acoustic structure of female calls varies significantly around their fertile period. Here, we used a combination of hormone measurements and acoustic analyses to determine whether female giant panda chirps have ...
Wiser A - - 2009
The aim of this study was to evaluate the affect of age at the time of orchidopexy on testicular sperm extraction (TESE) results among patients with a history of cryptorchidism and azoospermia. This retrospective study compared TESE results for couples undergoing IVF treatment, among two groups of patients. Group A ...
Canavese F - - 2009
INTRODUCTION: Recent data has indicated the usefulness of performing orchiopexy in the first years of life. In this study, we evaluated testicular function in young men operated on for cryptorchidism in the first year of life. To our knowledge, this is the first report on the effects of such an ...
Beets Gijs - - 2009
Fertility curves sometimes resemble sea waves. During periods that the fertility age patterns change, according to whatever reason, 'this sea' may become very turbulent. Also other sea-like phenomena, for example tsunamis, are discernible in fertility behaviour. This article gives a short overview of the relationships between age of the mother ...
Cardona Maya W??lter - - 2009
Although the effect of maternal age on fertility is well known, it is unclear whether paternal age also affects fertility. The aim of this retrospective study was to establish an association between the age of the individuals from Medellin, Colombia with semen volume, rapid progressive motility (a), total progressive motility ...
Au Phil Chi Khang - - 2010
Induced ovulation maximizes captive breeding success, increasing productivity and facilitating the contribution of otherwise infertile animals to the genetic pool. In marsupials, induced ovulation to produce fertile young is unknown. Here we present an induction protocol efficient in inducing non-cycling and non-reproductive females to cycle, mate, ovulate, and conceive. Ovulation ...
Serour Gamal - - 2010
OBJECTIVE: To estimate the live-birth and miscarriage rates in 1-year age increments for women aged ≥40 years undergoing in vitro fertilization or intracytoplasmic sperm injection (ICSI-IVF) with autologous oocytes. DESIGN: Retrospective database and chart analysis. SETTING: Egyptian IVF and embryo transfer center. PATIENT(S): One thousand six hundred forty-five women aged ...
Kumar Davendra - - 2010
A study was conducted to evaluate the semen production and sperm motion characteristics of ram lambs by computer-aided semen analysis technique. Eight Malpura rams were raised under intensive management system and were trained for semen collection at a weekly interval from the age of 6 months. Rams were scheduled for ...
Rako L - - 2009
In insects including Drosophila melanogaster, females can overwinter at the adult stage by adopting a shallow reproductive diapause, but almost nothing is known about male reproductive diapause. In this study, we test for the maintenance of fertility in overwintering males from the eastern Australian D. melanogaster cline. Males from southern ...
La Vignera S - - 2009
Cryptorchidism is the most frequent defect of the male urogenital tract at birth. It represents a risk factor for primitive testiculopathy associated with long-term complications (infertility, testicular neoplasia, and hormonal changes). An only consensus exists: "children with bilateral cryptorchidism who are not treated in early age are certainly set to ...
Eltigani Eltigani E - - 2009
Egypt and Tunisia began their fertility transition at almost identical fertility levels and at roughly the same time period, yet the difference in the pace of decline has been such that the total fertility rate (TFR) in Tunisia reached replacement level by the year 2001, whereas the TFR in Egypt ...
Gögele Martin - - 2009
Stelvio, Martello and Curon, three villages of the Venosta Valley, South Tyrol (Italy), were recently included in a large genetic survey because of their isolation. This study focuses on the long-term reproductive behaviour of these villages. Family size, age at marriage and marital fertility were estimated based on a genealogy ...
Goff K - - 2009
To determine whether sperm derived from the vas deferens could be retrieved and successfully cryopreserved, testes were collected from 20 rhesus macaques (Macaca mulatta). The males ranged in age from 3 to 19 yr with an average age of 8.5 yr. No sperm was obtained from three animals that were ...
Wedell Nina - - 2009
Sexual conflict can promote rapid evolution of male and female reproductive traits. Males of many polyandrous butterflies transfer nutrients at mating that enhances female fecundity, but generates sexual conflict over female remating due to sperm competition. Butterflies produce both normal fertilizing sperm and large numbers of non-fertile sperm. In the ...
Cornwallis Charlie K - - 2009
An important predictor of male fitness is the fertilizing efficiency of their ejaculates. Ejaculates are costly to produce and males are predicted to devote greater resources to copulations with reproductively superior females. It is well established that males allocate different numbers of sperm to ejaculates. However, less is known about ...
Schneider M I - - 2009
Few ecotoxicological studies have used life table analysis to evaluate the toxicity of pesticides on beneficial organisms. This study is the first report of the effect of the herbicide glyphosate on a predator insect, Chrysoperla externa, using a demographic approach. This predator is associated to soybean pests and has a ...
Shenk Mary K - - 2009
Over the last three decades many authors have addressed the demographic transition from the perspective of evolutionary theory. Some authors have emphasized parental investment factors such as the costs of raising children, others have emphasized the effects of mortality and other forms of risk, and others have emphasized the biased ...
Hawkes Kristen - - 2009
A grandmother hypothesis may explain why humans evolved greater longevity while continuing to end female fertility at about the same age as do the other great apes. With that grandmother hypothesis in mind, we sought to compare age-specific mortality and fertility rates between humans and chimpanzees, our closest living relatives, ...
Chotirmall S H - - 2009
Infertility rates among males with cystic fibrosis (CF) approximate 97%. No information is currently available within Ireland determining an understanding of fertility issues and the best methods of information provision to this specialized group. This study aimed to determine understanding and preferred approaches to information provision on fertility issues to ...
Crawshaw M A - - 2009
Discussion and management of potential reproductive health sequelae of adolescent cancer are essential and challenging components of care for the multidisciplinary team. Despite this, research has been limited to specific experiences (e.g. sperm banking) or fertility-related concerns of adult survivors. This grounded theory study of 38 male and female survivors ...
Gagnon Alain - - 2009
Frontier populations provide exceptional opportunities to test the hypothesis of a trade-off between fertility and longevity. In such populations, mechanisms favoring reproduction usually find fertile ground, and if these mechanisms reduce longevity, demographers should observe higher postreproductive mortality among highly fertile women. We test this hypothesis using complete female reproductive ...
Vahidi Serajeldin - - 2009
This study aimed to determine the prevalence of lifetime and current primary infertility in Iran. The study was conducted in 2004-5 in all the 28 provinces of Iran. A cluster sampling method was used to select 10 783 women aged 19 to 49 years for the survey. Lifetime primary infertility ...
Baéza E - - 2009
The aim of this study was to determine the specific characteristics of carcass and meat from an old French chicken breed, the 'Géline de Touraine' (GT), characterised by a very slow-growing rate and usually slaughtered at 120 days of age. For this purpose, we compared the GT with an experimental ...
Billingsley Sunnee - - 2010
Fertility has unanimously declined across the entire post-communist region. This study explores the variation in fertility trends over time among these countries and assesses to what degree three explanations are applicable: second demographic transition (SDT), postponement transition (PPT) or reaction to the economic crisis. Moreover, on the basis of SDT ...
Ssebuliba, R N
There are 84 distinct cultivars of highland bananas (Musa   spp.) in Uganda, grouped in five clone sets and it is not known which among these are female fertile. The objective of the study reported herein was to identify female fertile highland bananas that can be used in a cross ...
Trsinar Bojan - - 2009
OBJECTIVES: The aim of the study was to compare fertility potential in patients who had been operated upon in childhood because of unilateral or bilateral cryptorchidism. METHODS: The study covered 68 men (age 25-30 years) with a history of unilateral (49) or bilateral orchidopexy (Mandat et al. in Eur J ...
Stradaioli G - - 2009
Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a selenoperoxidase accounting for most of the selenium content in mammalian testis, which has been found to be linked to fertility in humans. In this study, we addressed the issue whether PHGPx content in spermatozoa could be a predictive index of fertilization capacity for ...
Cremin I - - 2009
OBJECTIVE: To identify reporting biases and to determine the influence of inconsistent reporting on observed trends in the timing of age at first sex and age at marriage. METHODS: Longitudinal data from three rounds of a population-based cohort in eastern Zimbabwe were analysed. Reports of age at first sex and ...
Mukhopadhyay Dyutiman - - 2010
OBJECTIVE: To compare the semen quality and age-specific changes in men between the 1980s and 2000s. DESIGN: Prospective study. SETTING: Andrology laboratory, University of Calcutta, India. PATIENT(S): A semen sample was obtained from 3729 men presenting for infertility problems in two distinct decades, that is, between 1981-85 and 2000-2006. INTERVENTION(S): ...
Evans Jonathan P - - 2009
Sperm competition theory predicts that males should tailor their investment in ejaculates according to the number of rival males competing to fertilize a female's eggs. Research spanning several taxa supports this prediction by showing that males are often sensitive to the level of sperm competition and adjust their investment in ...
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