Showing papers on "Fertility published in 2006"
TL;DR: Fertility preservation is often possible in people undergoing treatment for cancer and should be considered as early as possible during treatment planning, to preserve the full range of options.
Abstract: Purpose To develop guidance to practicing oncologists about available fertility preservation methods and related issues in people treated for cancer. Methods An expert panel and a writing committee were formed. The questions to be addressed by the guideline were determined, and a systematic review of the literature from 1987 to 2005 was performed, and included a search of online databases and consultation with content experts. Results The literature review found many cohort studies, case series, and case reports, but relatively few randomized or definitive trials examining the success and impact of fertility preservation methods in people with cancer. Fertility preservation methods are used infrequently in people with cancer. Recommendations As part of education and informed consent before cancer therapy, oncologists should address the possibility of infertility with patients treated during their reproductive years and be prepared to discuss possible fertility preservation options or refer appropriate and interested patients to reproductive specialists. Clinician judgment should be employed in the timing of raising this issue, but discussion at the earliest possible opportunity is encouraged. Sperm and embryo cryopreservation are considered standard practice and are widely available; other available fertility preservation methods should be considered investigational and be performed in centers with the necessary expertise.
1,784 citations
29 Sep 2006
TL;DR: The cesarean delivery rate jumped 6 percent to another all-time high, whereas the rate of vaginal birth after previous cesAREan fell by 13 percent, and preterm and low birthweight rates continued their steady rise.
Abstract: Objectives—This report presents 2004 data on U.S. births according to a wide variety of characteristics. Data are presented for maternal demographic characteristics including age, live-birth order, race, Hispanic origin, marital status, and educational attainment; maternal lifestyle and health characteristics (medical risk factors, weight gain, and tobacco use); medical care utilization by pregnant women (prenatal care, obstetric procedures, characteristics of labor and/or delivery, attendant at birth, and method of delivery); and infant characteristics (period of gestation, birthweight, Apgar score, congenital anomalies, and multiple births). Also presented are birth and fertility rates by age, live-birth order, race, Hispanic origin, and marital status. Selected data by mother's state of residence are shown, as well as data on month and day of birth, sex ratio, and age of father. Trends in fertility patterns and maternal and infant characteristics are described and interpreted. Methods—Descriptive tabulations of data reported on the birth certificates of the 4.1 million births that occurred in 2004 are presented.
676 citations
TL;DR: The various mechanisms that might underlie the link between excess adiposity and PCOS are considered – including the effects of differential insulin sensitivity, abnormal steroid hormone metabolism and adipocytokine secretion.
Abstract: The aetiology of Polycystic Ovary Syndrome (PCOS) is complex and multifactorial. There is much evidence, however, to suggest that adipose tissue plays an important role in the development and maintenance of PCOS pathology. There is a close correlation between adiposity and symptom severity in women with PCOS, and even modest reductions in weight generally translate into significant improvements in menstrual regularity, fertility and hyperandrogenic features. This review article considers the various mechanisms that might underlie this link between excess adiposity and PCOS - including the effects of differential insulin sensitivity, abnormal steroid hormone metabolism and adipocytokine secretion. Greater attention to the therapeutic options available to reduce the impact of excess adiposity on ovarian and metabolic function is essential to the management of PCOS.
509 citations
TL;DR: Some 30 countries today have fertility rates below 1.5 births per woman and the governments of each of these countries have reported to the United Nations that they consider this rate to be "too low" as discussed by the authors.
Abstract: Some 30 countries today have fertility rates below 1.5 births per woman. The governments of each of these countries have reported to the United Nations that they consider this rate to be "too low" (United Nations 2004). When fertility is moderately below replacement level the size of subsequent generations falls only slowly and if considered necessary there is an opportunity to supplement the generation size with migration. When fertility remains very low however the generation size falls rapidly and massive migration would be required to offset the decline (United Nations 2000). Hence we can think in terms of a "safety zone" for low fertility. Population dynamics tends to confirm the view of governments that the "safety zone" lies above 1.5 births per woman. (excerpt)
481 citations
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TL;DR: It is argued that school entry policies manipulate primarily the education of young women at risk of dropping out of school.
Abstract: This paper uses age-at-school-entry policies to identify the effect of female education on fertility and infant health. We focus on sharp contrasts in schooling, fertility, and infant health between women born just before and after the school entry date. School entry policies affect female education and the quality of a woman%u2019s mate and have generally small, but possibly heterogeneous, effects on fertility and infant health. We argue that school entry policies manipulate primarily the education of young women at risk of dropping out of school.
469 citations
TL;DR: This article used the GSS to examine the fertility of women born in the US but from different ethnic backgrounds and found that the number of siblings and number of parents are significant determinants of fertility, even after controlling for several individual and family level characteristics.
Abstract: This paper attempts to disentangle the direct effects of experience from those of culture in determining fertility. We use the GSS to examine the fertility of women born in the US but from different ethnic backgrounds. We take lagged values of the total fertility rate in the woman's country of ancestry as the cultural proxy and use the woman's number of siblings to capture her direct family experience. We find that both variables are significant determinants of fertility, even after controlling for several individual and family-level characteristics. (JEL: J13, J16, Z10)
433 citations
TL;DR: Prenatal sex determination followed by selective abortion of female fetuses is the most plausible explanation for the low sex ratio at birth in India.
396 citations
TL;DR: University students plan to have children at ages when female fertility is decreased without being sufficiently aware of the age-related decline in fertility, which increases the risk of involuntary infertility in this group, which is alarming in view of the great importance they put on parenthood.
Abstract: BACKGROUND: Postponing childbirth is becoming increasingly common in Western countries, especially among groups with higher education qualifications. It is relatively unknown to what extent women and men are aware of the age-related decline in female fertility. The aim was to investigate university students' intentions and attitudes to future parenthood and their awareness regarding female fertility. METHODS: Postal survey of a randomly selected sample of 222 female (74% response) and 179 male (60% response) university students. RESULTS: Female and male university students in Sweden have largely positive attitudes towards parenthood and want to have children. Women, in comparison to men, were significantly more concerned about problems related to combining work and children. Both women and men had overly optimistic perceptions of women's chances of becoming pregnant. About half of women intended to have children after age 35 years and were not sufficiently aware of the age-related decline of female fecundity in the late 30s. CONCLUSIONS: University students plan to have children at ages when female fertility is decreased without being sufficiently aware of the age-related decline in fertility. This increases the risk of involuntary infertility in this group, which is alarming in view of the great importance they put on parenthood.
391 citations
TL;DR: There was a dose–response relationship, and the BMI effect was stronger when the data were limited to couples with the highest-quality infertility data, suggesting that erectile dysfunction in older men does not explain the association.
Abstract: Background:Overweight and obese men have been reported to have lower sperm counts and hormonal changes, but data are lacking regarding effects on couple fertility.Methods:We examined the relationship between male body mass index (BMI) and infertility in couples enrolled in the Agricultural Health St
311 citations
TL;DR: In this paper, a norm-based explanation for the fertility transition in rural Bangladesh is provided, where norms are organized at the level of the religious group and interactions rarely cross religious boundaries.
306 citations
TL;DR: The evidence in the demographic and family planning literature of the range and diversity of the barriers to fertility regulation in many developing countries is reviewed in this article from a consumer perspective.
Abstract: The evidence in the demographic and family planning literature of the range and diversity of the barriers to fertility regulation in many developing countries is reviewed in this article from a consumer perspective. Barriers are defined as the constraining factors standing between women and the realistic availability of the technologies and correct information they need in order to decide whether and when to have a child. The barriers include limited method choice, financial costs, the status of women, medical and legal restrictions, provider bias, and misinformation. The presence or absence of barriers to fertility regulation is likely an important determinant of the pace of fertility decline or its delay in many countries. At the same time, barriers inhibit women's ability to avoid unintended pregnancy. Problems of quantifying barriers limit understanding of their importance. New ways to quantify them and to identify misinformation, which is often concealed in survey data, are needed for future research.
TL;DR: Wide disparities exist in the quality, availability, and delivery of infertility services between the developed and developing nations of the world.
TL;DR: High ROS is an independent marker of MFI, irrespective of whether these patients have normal or abnormal semen parameters, and the inclusion of ROS measurement as part of idiopathic infertility evaluation is suggested.
TL;DR: For example, this paper found that unmarried parents are much more likely to have had a child by a previous partner than married parents, and race/ ethnicity is strongly associated with multipartnered fertility as is mothers young age at first birth and fathers history of incarceration.
Abstract: Recent trends in marriage and fertility have increased the number of adults having children by more than 1 partner a phenomenon that we refer to as multipartnered fertility. This article uses data from the Fragile Families and Child Well-being Study to examine the prevalence and correlates of multipartnered fertility among urban parents of a recent birth cohort (N = 4300). We find that unmarried parents are much more likely to have had a child by a previous partner than married parents. Also race/ ethnicity is strongly associated with multipartnered fertility as is mothers young age at first birth and fathers history of incarceration. To the extent that childrearing across households diminishes parental resources multipartnered fertility has important consequences for childrens well-being. (authors)
TL;DR: With a prevalence of up to 90%, uterine adenomyosis is significantly associated with pelvic endometriosis and constitutes an important factor of sterility in endometRIosis presumably by impairing uterine sperm transport.
Abstract: BACKGROUND: The hypothesis is tested that there is a strong association between endometriosis and adenomyosis and that adenomyosis plays a role in causing infertility in women with endometriosis. METHODS. Magnetic resonance imaging of the uteri was performed in 160 women with and 67 women without endometriosis. The findings were correlated with the stage of the disease, the age of the women and the sperm count parameters of the respective partners. RESULTS: The posterior junctional zone (PJZ) was significantly thicker in women with endometriosis than in those without the disease (P < 0.001). There was a positive correlation of the diameter of the PJZ with the stage of the disease and the age of the patients. The PJZ was thicker in patients with endometriosis with fertile than in patients with subfertile partners. The prevalence of adenomyotic lesions in all 160 women with endometriosis was 79%. In women with endometriosis below an age of 36 years and fertile partners, the prevalence of adenomyosis was 90% (P < 0.01) CONCLUSIONS: With a prevalence of up to 90%, uterine adenomyosis is significantly associated with pelvic endometriosis and constitutes an important factor of sterility in endometriosis presumably by impairing uterine sperm transport.
TL;DR: The present review is designed to bring the clinician up to date with the most current understanding of the mechanisms that regulate sperm motility and to raise questions about how aberrations in these mechanisms could be the underlying causes of this pathology.
Abstract: Because it is generally accepted that a high percentage of poorly motile or immotile sperm will adversely affect male fertility, analysis of sperm motility is a central part of the evaluation of male fertility In spite of its importance to fertility, poor sperm motility remains only a description of a pathology whose underlying cause is typically poorly understood The present review is designed to bring the clinician up to date with the most current understanding of the mechanisms that regulate sperm motility and to raise questions about how aberrations in these mechanisms could be the underlying causes of this pathology
TL;DR: Sperm motility and concentration provide more accurate information than morphology (WHO and Tygerberg's criteria) during infertility evaluation, and redefining the reference values for concentration and morphology may significantly increase the importance of routine semen analysis.
TL;DR: There has been a significant decline in 12-month infertility among married women in the United States, which cannot be explained by changes in the composition of the population from 1982-2002.
TL;DR: African American women are more likely to seek infertility treatment after a longer duration of failed conception compared with Caucasian women, and African American, and Hispanic women areMore likely to have tubal factor infertility, a lower education level, and a lower household income compared with Caucasians.
TL;DR: This paper examined the evolution of completed fertility patterns for Swedish women born in 1925-1958 and made comparisons to women in neighbouring countries where the policies were not extended as much as in Sweden.
Abstract: From the mid-1960s to around 1980, Sweden extended its family policies that provide financial and in-kind support to families with children very quickly. The benefits were closely tied to previous work experience. Thus, women born in the 1950s faced markedly different incentives when making fertility choices compared to women born only 15–20 years earlier. This paper examines the evolution of completed fertility patterns for Swedish women born in 1925–1958 and makes comparisons to women in neighbouring countries where the policies were not extended as much as in Sweden. The results suggest that the extension of the policy raised the level of fertility, shortened the spacing of births, and induced fluctuations in the period fertility rates, but it did not change the negative relationship between women’s educational level and completed fertility.
TL;DR: Recent research into diets specifically designed to stimulate insulin secretion, increase progesterone production by the corpus luteum and enhance the antiluteolytic mechanism is providing new opportunities for improving dairy cow fertility with associated benefits for suckling beef cows.
TL;DR: It is found that observed mating success was generally a good predictor of paternity success, that high-ranking males had higher paternity success than lower- ranking males, and that male density and male rank stability contributed to variance in male paternity success.
TL;DR: This article conducted a meta-analysis of the existing literature on the relation between fertility and women's employment at the micro-level and found a high variation in the studied effects among the institutional settings, reflecting the existence of a north-south gradient.
Abstract: Our research objective was to systematise the existing literature on the relation between fertility and women’s employment at the micro-level. Instead of carrying out a traditional literature review, we conducted a meta-analysis. This allowed us to compare estimates from different studies standardised for the country analysed, the method applied, control variables used and sample selected. We focused on two effects: the impact of work on fertility and the impact of young children on employment entry. First, we found a high variation in the studied effects among the institutional settings, reflecting the existence of a north–south gradient. Second, we observed a significant change in the effects over time. Finally, we demonstrated that a failure to account for the respondent’s social background, partner and job characteristics tends to produce a bias in the estimated effects.
01 May 2006
TL;DR: The reproductive experiences of men and women 15-44 years of age in the United States vary significantly, and often sharply, by demographic characteristics such as education, income, and Hispanic origin and race.
Abstract: Objective This report presents national estimates of fertility, family formation, contraceptive use, and father involvement indicators among males 15-44 years of age in the United States in 2002 from Cycle 6 of the National Survey of Family Growth (NSFG). Data are also shown for women for purposes of comparison. Methods Descriptive tables of numbers and percentages are presented. Data were collected through in-person interviews of the household population 15-44 years of age in the United States between March 2002 and March 2003. The sample included 7,643 females and 4,928 males. This report focuses primarily on data from the male sample, but compares findings with the female data whenever appropriate. The overall response rate for Cycle 6 of the NSFG was 79 percent, and the response rate for men was 78 percent. Results This report covers a wide range of topics including first sexual intercourse and its timing in relation to marriage; contraceptive use; wantedness of births in the past 5 years; marital and cohabiting status at first birth; living arrangement of fathers with their children; father's activities with children they live with and those they do not live with; HIV-risk related behaviors; and infertility services. Conclusion The reproductive experiences of men and women 15-44 years of age in the United States vary significantly, and often sharply, by demographic characteristics such as education, income, and Hispanic origin and race.
TL;DR: This commentary argues that adverse health outcomes should be weighed up against advantages for children born to older parents, mindful that these societal advantages are likely to change over time.
Abstract: Average paternal age in the UK is increasing. The public health implications of this trend have not been widely anticipated or debated. This commentary aims to contribute to such a debate. Accumulated chromosomal aberrations and mutations occurring during the maturation of male germ cells are thought to be responsible for the increased risk of certain conditions with older fathers. Growing evidence shows that the offspring of older fathers have reduced fertility and an increased risk of birth defects, some cancers, and schizophrenia. Adverse health outcomes should be weighed up against advantages for children born to older parents, mindful that these societal advantages are likely to change over time.
TL;DR: Investigation of whether important racial, ethnic, or socioeconomic status health disparities exist in infertility, impaired fecundity, or infertility treatment found that older women, non-Hispanic white women, and women who are more educated are more likely to have ever received treatment.
TL;DR: Signals from the transforming growth factor-beta superfamily of proteins are vital for governance of testis development and spermatogenesis, and current understanding of the mechanisms and processes in which they have been implicated with a focus on the fetal and juvenile testis is discussed.
Abstract: To achieve and maintain fertility, the adult mammalian testis produces many generations of sperm. While testicular integrity is established in the fetus and develops further in juvenile life, sperm production does not ensue until much later in life, following the onset of puberty. Signals from the transforming growth factor-beta superfamily of proteins are vital for governance of testis development and spermatogenesis, and this review discusses our current understanding of the mechanisms and processes in which they have been implicated with a focus on the fetal and juvenile testis.
TL;DR: Since the one child family policy began in China, the total birth rate and preferred family size have decreased, and a gross imbalance in the sex ratio has emerged.
Abstract: Objectives To examine the impact of the one child family policy in China on fertility, preferred family size, and sex ratio. Design Secondary analysis of data from the Chinese cross sectional national family planning and reproductive health survey, 2001. Interviews of representative sample of women aged 15-49. Results Data were obtained from 39 585 women, with a total of 73 202 pregnancies and 56 830 live births. The average fertility rate in women over 35 (n = 17 078) was 1.94 (2.1 in rural areas and 1.4 in urban areas) and for women under 35 (n = 11 543) 1.73 (1.25 and 1.79). Smaller families were associated with younger age, higher level of education, and living in an urban area. The male to female ratio was 1.15 and rose from 1.11 in 1980-9 to 1.23 for 1996-2001. Most women wanted small families: 35% preferred one child and 57% preferred two. Conclusion Since the one child family policy began, the total birth rate and preferred family size have decreased, and a gross imbalance in the sex ratio has emerged.
TL;DR: This work reviews the research on low fertility through the predominant frameworks and theories used to explain it and focuses on the ability of theory to situate previous and future findings and concludes with directions for furthur research.
Abstract: In the past few decades, demographic concerns have shifted from rapid population growth fueled by high fertility to concerns of population decline produced by very low, sub-replacement fertility levels. Once considered a problem unique to Europe or developed nations, concerns now center on the global spread of low fertility. Nearly half of the world's population now lives in countries with fertility at or below replacement levels. Further, by the mid-twenty-first century three of four countries now described as developing are projected to reach or slip below replacement fertility. We review the research on low fertility through the predominant frameworks and theories used to explain it. These explanations range from decomposition and proximate determinant frameworks to grand theories on the fundamental causes underlying the pervasiveness and spread of low fertility. We focus on the ability of theory to situate previous and future findings and conclude with directions for furthur research.
01 Jan 2006
TL;DR: In this paper, the authors investigate the emergence and persistence of low and particularly lowest-low fertility in Europe analyze its demographic patterns and socioeconomic determinants and address the factors that underlie the divergence of fertility levels in Europe and developed countries more generally.
Abstract: In this paper we investigate the emergence and persistence of low and particularly lowest-low fertility in Europe analyze its demographic patterns and socioeconomic determinants and address the factors that underlie the divergence of fertility levels in Europe and developed countries more generally. The central thrust of our argument is that the emergence of lowest-low fertility in Europe is due to the combination of four distinct demographic and behavioral factors. First economic and social changes have made the postponement of fertility a rational response for individuals. Second social interaction processes affecting the timing of fertility have rendered the population response to these new socioeconomic conditions substantially larger than the direct individual responses. As a consequence modest socioeconomic changes can explain the rapid and persistent postponement transitions from early to late age-patterns of fertility that have been associated with recent trends towards low and lowest-low fertility. Third demographic distortions of period fertility measures caused by the postponement of fertility and changes in the parity-composition of the population have reduced the level of period fertility indicators below the associated level of cohort fertility (for discussion of this technical aspect see Bongaarts and Feeney 1998; Kohler and Ortega 2002). Fourth institutional settings in Southern Central and Eastern European countries have favored an overall low quantum of fertility. Moreover this institutional setting has caused particularly large reductions in completed fertility in lowest-low fertility countries due to the delay of childbearing. (excerpt)