The Experts below are selected from a list of 105630 Experts worldwide ranked by ideXlab platform
Walter C Willett - One of the best experts on this subject based on the ideXlab platform.
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a prospective study of dietary carbohydrate quantity and quality in relation to risk of ovulatory Infertility
European Journal of Clinical Nutrition, 2009Co-Authors: Jorge E Chavarro, Walter C Willett, Janet W Richedwards, Bernard RosnerAbstract:To evaluate whether the amount or quality of carbohydrate in diet is associated with ovulatory Infertility. In total, 18 555 married, premenopausal women without a history of Infertility were followed as they attempted a pregnancy or became pregnant during an 8-year period. Diet was assessed two times during follow-up using a validated food-frequency questionnaire and prospectively related to the incidence of Infertility due ovulatory disorder. During follow-up, 438 women reported ovulatory Infertility. Total carbohydrate intake and dietary glycemic load were positively related to ovulatory Infertility in analyses adjusted for age, body mass index, smoking, parity, physical activity, recency of contraception, total energy intake, protein intake and other dietary variables. The multivariable-adjusted risk ratio (RR) (95% confidence interval (CI)) of ovulatory Infertility comparing the highest-to-lowest quintile of total carbohydrate intake was 1.91 (1.27–3.02). The corresponding RR (95% CI) for dietary glycemic load was 1.92 (1.26–2.92). Dietary glycemic index was positively related to ovulatory Infertility only among nulliparous women. Intakes of fiber from different sources were unrelated to ovulatory Infertility risk. The amount and quality of carbohydrate in diet may be important determinants of ovulation and fertility in healthy women.
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use of multivitamins intake of b vitamins and risk of ovulatory Infertility
Fertility and Sterility, 2008Co-Authors: Jorge E Chavarro, Walter C Willett, Janet W Richedwards, Bernard RosnerAbstract:Objective To examine whether use of multivitamins and intake of specific nutrients in multivitamins is associated with ovulatory Infertility. Design A prospective cohort study. Setting The Nurses' Health Study II. Patient(s) Eighteen thousand five hundred fifty-five married, premenopausal women without a history of Infertility who attempted a pregnancy or became pregnant between 1991 and 1999. Intervention(s) None, observational study. Main Outcome Measure(s) Incident reports of Infertility caused by anovulation. Result(s) During 8 years of follow-up, 438 women reported Infertility caused by ovulatory disorder. There was an inverse association between frequency of multivitamin use and ovulatory Infertility. The multivariate-adjusted relative risk (95% confidence interval) of ovulatory Infertility was 0.88 (0.60, 1.28) for women consuming two tablets per week or less, 0.69 (0.51, 0.95) for women consuming three to five tablets per week, and 0.59 (0.46, 0.75) for women consuming six or more tablets per week, when compared with women who did not use these supplements ( P , trend Conclusion(s) Regular use of multivitamin supplements may decrease the risk of ovulatory Infertility.
Gretchen A Stevens - One of the best experts on this subject based on the ideXlab platform.
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national regional and global trends in Infertility prevalence since 1990 a systematic analysis of 277 health surveys
PLOS Medicine, 2012Co-Authors: Maya Mascarenhas, Ties Boerma, Seth Flaxman, Sheryl Vanderpoel, Gretchen A StevensAbstract:Background Global, regional, and national estimates of prevalence of and tends in Infertility are needed to target prevention and treatment efforts. By applying a consistent algorithm to demographic and reproductive surveys available from developed and developing countries, we estimate Infertility prevalence and trends, 1990 to 2010, by country and region. Methods and Findings We accessed and analyzed household survey data from 277 demographic and reproductive health surveys using a consistent algorithm to calculate Infertility. We used a demographic Infertility measure with live birth as the outcome and a 5-y exposure period based on union status, contraceptive use, and desire for a child. We corrected for biases arising from the use of incomplete information on past union status and contraceptive use. We used a Bayesian hierarchical model to estimate prevalence of and trends in Infertility in 190 countries and territories. In 2010, among women 20–44 y of age who were exposed to the risk of pregnancy, 1.9% (95% uncertainty interval 1.7%, 2.2%) were unable to attain a live birth (primary Infertility). Out of women who had had at least one live birth and were exposed to the risk of pregnancy, 10.5% (9.5%, 11.7%) were unable to have another child (secondary Infertility). Infertility prevalence was highest in South Asia, Sub-Saharan Africa, North Africa/Middle East, and Central/Eastern Europe and Central Asia. Levels of Infertility in 2010 were similar to those in 1990 in most world regions, apart from declines in primary and secondary Infertility in Sub-Saharan Africa and primary Infertility in South Asia (posterior probability [pp] ≥0.99). Although there were no statistically significant changes in the prevalence of Infertility in most regions amongst women who were exposed to the risk of pregnancy, reduced child-seeking behavior resulted in a reduction of primary Infertility among all women from 1.6% to 1.5% (pp = 0.90) and a reduction of secondary Infertility among all women from 3.9% to 3.0% (pp>0.99) from 1990 to 2010. Due to population growth, however, the absolute number of couples affected by Infertility increased from 42.0 million (39.6 million, 44.8 million) in 1990 to 48.5 million (45.0 million, 52.6 million) in 2010. Limitations of the study include gaps in survey data for some countries and the use of proxies to determine exposure to pregnancy. Conclusions We analyzed demographic and reproductive household survey data to reveal global patterns and trends in Infertility. Independent from population growth and worldwide declines in the preferred number of children, we found little evidence of changes in Infertility over two decades, apart from in the regions of Sub-Saharan Africa and South Asia. Further research is needed to identify the etiological causes of these patterns and trends. Please see later in the article for the Editors' Summary
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national regional and global trends in Infertility prevalence since 1990 a systematic analysis of 277 health surveys
PLOS Medicine, 2012Co-Authors: Maya Mascarenhas, Ties Boerma, Seth Flaxman, Sheryl Vanderpoel, Gretchen A StevensAbstract:BACKGROUND: Global regional and national estimates of prevalence of and tends in Infertility are needed to target prevention and treatment efforts. By applying a consistent algorithm to demographic and reproductive surveys available from developed and developing countries we estimate Infertility prevalence and trends 1990 to 2010 by country and region. METHODS AND FINDINGS: We accessed and analyzed household survey data from 277 demographic and reproductive health surveys using a consistent algorithm to calculate Infertility. We used a demographic Infertility measure with live birth as the outcome and a 5-y exposure period based on union status contraceptive use and desire for a child. We corrected for biases arising from the use of incomplete information on past union status and contraceptive use. We used a Bayesian hierarchical model to estimate prevalence of and trends in Infertility in 190 countries and territories. In 2010 among women 20-44 y of age who were exposed to the risk of pregnancy 1.9% (95% uncertainty interval 1.7% 2.2%) were unable to attain a live birth (primary Infertility). Out of women who had had at least one live birth and were exposed to the risk of pregnancy 10.5% (9.5% 11.7%) were unable to have another child (secondary Infertility). Infertility prevalence was highest in South Asia Sub-Saharan Africa North Africa/Middle East and Central/Eastern Europe and Central Asia. Levels of Infertility in 2010 were similar to those in 1990 in most world regions apart from declines in primary and secondary Infertility in Sub-Saharan Africa and primary Infertility in South Asia (posterior probability [pp] >/=0.99). Although there were no statistically significant changes in the prevalence of Infertility in most regions amongst women who were exposed to the risk of pregnancy reduced child-seeking behavior resulted in a reduction of primary Infertility among all women from 1.6% to 1.5% (pp=0.90) and a reduction of secondary Infertility among all women from 3.9% to 3.0% (pp>0.99) from 1990 to 2010. Due to population growth however the absolute number of couples affected by Infertility increased from 42.0 million (39.6 million 44.8 million) in 1990 to 48.5 million (45.0 million 52.6 million) in 2010. Limitations of the study include gaps in survey data for some countries and the use of proxies to determine exposure to pregnancy. CONCLUSIONS: We analyzed demographic and reproductive household survey data to reveal global patterns and trends in Infertility. Independent from population growth and worldwide declines in the preferred number of children we found little evidence of changes in Infertility over two decades apart from in the regions of Sub-Saharan Africa and South Asia. Further research is needed to identify the etiological causes of these patterns and trends.
Ashok Agarwal - One of the best experts on this subject based on the ideXlab platform.
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a unique view on male Infertility around the globe
Reproductive Biology and Endocrinology, 2015Co-Authors: Ashok Agarwal, Alaa Hamada, Aditi Mulgund, Michelle ChyatteAbstract:Infertility affects an estimated 15% of couples globally, amounting to 48.5 million couples. Males are found to be solely responsible for 20-30% of Infertility cases and contribute to 50% of cases overall. However, this number does not accurately represent all regions of the world. Indeed, on a global level, there is a lack of accurate statistics on rates of male Infertility. Our report examines major regions of the world and reports rates of male Infertility based on data on female Infertility. Our search consisted of systematic reviews, meta-analyses, and population-based studies by searching the terms “epidemiology, male Infertility, and prevalence.” We identified 16 articles for detailed study. We typically used the assumption that 50% of all cases of Infertility are due to female factors alone, 20-30% are due to male factors alone, and the remaining 20-30% are due to a combination of male and female factors. Therefore, in regions of the world where male factor or rates of male Infertility were not reported, we used this assumption to calculate general rates of male factor Infertility. Our calculated data showed that the distribution of Infertility due to male factor ranged from 20% to 70% and that the percentage of infertile men ranged from 2·5% to 12%. Infertility rates were highest in Africa and Central/Eastern Europe. Additionally, according to a variety of sources, rates of male Infertility in North America, Australia, and Central and Eastern Europe varied from 4 5-6%, 9%, and 8-12%, respectively. This study demonstrates a novel and unique way to calculate the distribution of male Infertility around the world. According to our results, at least 30 million men worldwide are infertile with the highest rates in Africa and Eastern Europe. Results indicate further research is needed regarding etiology and treatment, reduce stigma & cultural barriers, and establish a more precise calculation.
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the genetic causes of male factor Infertility a review
Fertility and Sterility, 2010Co-Authors: Katherine Oflynn L Obrien, Alex C Varghese, Ashok AgarwalAbstract:Objective To illustrate the necessity for an enhanced understanding of the genetic basis of male factor Infertility, to present a comprehensive synopsis of these genetic elements, and to review techniques being utilized to produce new insights in fertility research. Background Male factor Infertility is a complex disorder that affects a large sector of the population; however, many of its etiologies are unknown. By elucidating the underlying genetic basis of infertile phenotypes, it may be possible to discover the causes of Infertility and determine effective treatments for patients. Method(s) The PubMed database was consulted for the most relevant papers published in the last 3 years pertaining to male factor Infertility using the keywords "genetics" and "male Infertility." Result(s) Advances have been made in the characterization of the roles of specific genes, but further research is necessary before these results can be used as guidelines for diagnosing and treating male factor Infertility. The accurate transmission of epigenetic information also has considerable influence on fertility in males and on the fertility of their offspring. Conclusion(s) Analysis of the genetic factors that impact male factor Infertility will provide valuable insights into the creation of targeted treatments for patients and the determination of the causes of idiopathic Infertility. Novel technologies that analyze the influence of genetics from a global perspective may lead to further developments in the understanding of the etiology of male factor Infertility through the identification of specific infertile phenotype signatures.
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the role of varicocele repair in the new era of assisted reproductive technology
Clinics, 2008Co-Authors: Marcello Cocuzza, Frances Monette Bragais, Ashok AgarwalAbstract:Infertility affects 10-15% of couples who are trying to conceive, and half of the cases are due to male Infertility. Intracytoplasmic sperm injection is increasingly being used to overcome multiple sperm deficiencies. Due to its effectiveness, some have proposed ICSI as a solution for all cases of male Infertility, regardless of the cause. Hence, even men with potentially treatable causes of Infertility have sought the aid of assisted reproductive technology, rather than undergo specific therapies to treat their Infertility. Varicoceles are the most frequent physical finding in infertile men; indeed, they may be responsible for nearly one-third of cases of male Infertility. Varicocele management, however, has always been a controversial issue because very few randomized, controlled studies have been performed to examine varicocelectomy as an Infertility treatment. Significant evidence suggests that varicoceles have a harmful effect on the testis and that varicocelectomy can not only prevent progressive decline in testicular function but also reverse the damage. However, the degree to which varicocele repair improves pregnancy rates and the success of assisted reproductive technology remains controversial.
Maya Mascarenhas - One of the best experts on this subject based on the ideXlab platform.
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national regional and global trends in Infertility prevalence since 1990 a systematic analysis of 277 health surveys
PLOS Medicine, 2012Co-Authors: Maya Mascarenhas, Ties Boerma, Seth Flaxman, Sheryl Vanderpoel, Gretchen A StevensAbstract:Background Global, regional, and national estimates of prevalence of and tends in Infertility are needed to target prevention and treatment efforts. By applying a consistent algorithm to demographic and reproductive surveys available from developed and developing countries, we estimate Infertility prevalence and trends, 1990 to 2010, by country and region. Methods and Findings We accessed and analyzed household survey data from 277 demographic and reproductive health surveys using a consistent algorithm to calculate Infertility. We used a demographic Infertility measure with live birth as the outcome and a 5-y exposure period based on union status, contraceptive use, and desire for a child. We corrected for biases arising from the use of incomplete information on past union status and contraceptive use. We used a Bayesian hierarchical model to estimate prevalence of and trends in Infertility in 190 countries and territories. In 2010, among women 20–44 y of age who were exposed to the risk of pregnancy, 1.9% (95% uncertainty interval 1.7%, 2.2%) were unable to attain a live birth (primary Infertility). Out of women who had had at least one live birth and were exposed to the risk of pregnancy, 10.5% (9.5%, 11.7%) were unable to have another child (secondary Infertility). Infertility prevalence was highest in South Asia, Sub-Saharan Africa, North Africa/Middle East, and Central/Eastern Europe and Central Asia. Levels of Infertility in 2010 were similar to those in 1990 in most world regions, apart from declines in primary and secondary Infertility in Sub-Saharan Africa and primary Infertility in South Asia (posterior probability [pp] ≥0.99). Although there were no statistically significant changes in the prevalence of Infertility in most regions amongst women who were exposed to the risk of pregnancy, reduced child-seeking behavior resulted in a reduction of primary Infertility among all women from 1.6% to 1.5% (pp = 0.90) and a reduction of secondary Infertility among all women from 3.9% to 3.0% (pp>0.99) from 1990 to 2010. Due to population growth, however, the absolute number of couples affected by Infertility increased from 42.0 million (39.6 million, 44.8 million) in 1990 to 48.5 million (45.0 million, 52.6 million) in 2010. Limitations of the study include gaps in survey data for some countries and the use of proxies to determine exposure to pregnancy. Conclusions We analyzed demographic and reproductive household survey data to reveal global patterns and trends in Infertility. Independent from population growth and worldwide declines in the preferred number of children, we found little evidence of changes in Infertility over two decades, apart from in the regions of Sub-Saharan Africa and South Asia. Further research is needed to identify the etiological causes of these patterns and trends. Please see later in the article for the Editors' Summary
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national regional and global trends in Infertility prevalence since 1990 a systematic analysis of 277 health surveys
PLOS Medicine, 2012Co-Authors: Maya Mascarenhas, Ties Boerma, Seth Flaxman, Sheryl Vanderpoel, Gretchen A StevensAbstract:BACKGROUND: Global regional and national estimates of prevalence of and tends in Infertility are needed to target prevention and treatment efforts. By applying a consistent algorithm to demographic and reproductive surveys available from developed and developing countries we estimate Infertility prevalence and trends 1990 to 2010 by country and region. METHODS AND FINDINGS: We accessed and analyzed household survey data from 277 demographic and reproductive health surveys using a consistent algorithm to calculate Infertility. We used a demographic Infertility measure with live birth as the outcome and a 5-y exposure period based on union status contraceptive use and desire for a child. We corrected for biases arising from the use of incomplete information on past union status and contraceptive use. We used a Bayesian hierarchical model to estimate prevalence of and trends in Infertility in 190 countries and territories. In 2010 among women 20-44 y of age who were exposed to the risk of pregnancy 1.9% (95% uncertainty interval 1.7% 2.2%) were unable to attain a live birth (primary Infertility). Out of women who had had at least one live birth and were exposed to the risk of pregnancy 10.5% (9.5% 11.7%) were unable to have another child (secondary Infertility). Infertility prevalence was highest in South Asia Sub-Saharan Africa North Africa/Middle East and Central/Eastern Europe and Central Asia. Levels of Infertility in 2010 were similar to those in 1990 in most world regions apart from declines in primary and secondary Infertility in Sub-Saharan Africa and primary Infertility in South Asia (posterior probability [pp] >/=0.99). Although there were no statistically significant changes in the prevalence of Infertility in most regions amongst women who were exposed to the risk of pregnancy reduced child-seeking behavior resulted in a reduction of primary Infertility among all women from 1.6% to 1.5% (pp=0.90) and a reduction of secondary Infertility among all women from 3.9% to 3.0% (pp>0.99) from 1990 to 2010. Due to population growth however the absolute number of couples affected by Infertility increased from 42.0 million (39.6 million 44.8 million) in 1990 to 48.5 million (45.0 million 52.6 million) in 2010. Limitations of the study include gaps in survey data for some countries and the use of proxies to determine exposure to pregnancy. CONCLUSIONS: We analyzed demographic and reproductive household survey data to reveal global patterns and trends in Infertility. Independent from population growth and worldwide declines in the preferred number of children we found little evidence of changes in Infertility over two decades apart from in the regions of Sub-Saharan Africa and South Asia. Further research is needed to identify the etiological causes of these patterns and trends.
Janet W Richedwards - One of the best experts on this subject based on the ideXlab platform.
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a prospective study of dietary carbohydrate quantity and quality in relation to risk of ovulatory Infertility
European Journal of Clinical Nutrition, 2009Co-Authors: Jorge E Chavarro, Walter C Willett, Janet W Richedwards, Bernard RosnerAbstract:To evaluate whether the amount or quality of carbohydrate in diet is associated with ovulatory Infertility. In total, 18 555 married, premenopausal women without a history of Infertility were followed as they attempted a pregnancy or became pregnant during an 8-year period. Diet was assessed two times during follow-up using a validated food-frequency questionnaire and prospectively related to the incidence of Infertility due ovulatory disorder. During follow-up, 438 women reported ovulatory Infertility. Total carbohydrate intake and dietary glycemic load were positively related to ovulatory Infertility in analyses adjusted for age, body mass index, smoking, parity, physical activity, recency of contraception, total energy intake, protein intake and other dietary variables. The multivariable-adjusted risk ratio (RR) (95% confidence interval (CI)) of ovulatory Infertility comparing the highest-to-lowest quintile of total carbohydrate intake was 1.91 (1.27–3.02). The corresponding RR (95% CI) for dietary glycemic load was 1.92 (1.26–2.92). Dietary glycemic index was positively related to ovulatory Infertility only among nulliparous women. Intakes of fiber from different sources were unrelated to ovulatory Infertility risk. The amount and quality of carbohydrate in diet may be important determinants of ovulation and fertility in healthy women.
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use of multivitamins intake of b vitamins and risk of ovulatory Infertility
Fertility and Sterility, 2008Co-Authors: Jorge E Chavarro, Walter C Willett, Janet W Richedwards, Bernard RosnerAbstract:Objective To examine whether use of multivitamins and intake of specific nutrients in multivitamins is associated with ovulatory Infertility. Design A prospective cohort study. Setting The Nurses' Health Study II. Patient(s) Eighteen thousand five hundred fifty-five married, premenopausal women without a history of Infertility who attempted a pregnancy or became pregnant between 1991 and 1999. Intervention(s) None, observational study. Main Outcome Measure(s) Incident reports of Infertility caused by anovulation. Result(s) During 8 years of follow-up, 438 women reported Infertility caused by ovulatory disorder. There was an inverse association between frequency of multivitamin use and ovulatory Infertility. The multivariate-adjusted relative risk (95% confidence interval) of ovulatory Infertility was 0.88 (0.60, 1.28) for women consuming two tablets per week or less, 0.69 (0.51, 0.95) for women consuming three to five tablets per week, and 0.59 (0.46, 0.75) for women consuming six or more tablets per week, when compared with women who did not use these supplements ( P , trend Conclusion(s) Regular use of multivitamin supplements may decrease the risk of ovulatory Infertility.
