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## An epidemiologic investigation of the relationship between DBCP contamination in drinking water and birth rates in Fresno County, California.

Wong, O; Whorton, M D; Gordon, N; Morgan, R W
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.06%
This report describes an epidemiologic investigation of the relationship between DBCP (dibromochloropropane) contamination in drinking water and birth rates between 1978 and 1982 in Fresno County, California. Census tracts in the county were categorized according to DBCP level in their drinking water. Standardized birth ratios and relative birth ratios (adjusted for age, race, per cent Hispanic, and parity) were calculated for these census tracts. No relation between birth ratios and DBCP contamination in drinking water was found.

## Increasing Cesarean Birth Rates: A Clash of Cultures?

Moore, Mary Lou
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.09%
Cesarean birth rates in the United States reached a high of 27.6% in 2003, a 6% increase over 2002. A cultural conflict appears to exist between the views of those who believe that birth is normal and many cesareans are unnecessary and the views of those who feel that higher rates are justifiable. Childbirth educators can share cultural concepts of normal birth in their classroom.

## Rising Preterm Birth Rates, 1989-2004: Changing Demographics or Changing Obstetric Practice?

VanderWeele, Tyler J.; Lantos, John D.; Lauderdale, Diane S.
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.2%
Preterm birth rates are higher in the United States than in most industrialized countries, and have been rising steadily. Some attribute these trends to changing demographics, with more older mothers, more infertility, and more multiple births. Others suggest that changes in obstetrics are behind the trends. We sought to determine what the preterm birth rate in 2004 would have been if demographic factors had not changed since 1989. We examined complete US birth certificate files from 1989 and 2004 and used logistic regression models to estimate what the 2004 preterm birth rates (overall, spontaneous, and medically induced) would have been if maternal age, race, nativity, gravidity, marital status, and education among childbearing women had not changed since 1989. While the overall preterm births increased from 11.2% to 12.8% from 1989-2004, medically induced rates increased 94%, from 3.4% to 6.6%, and spontaneous rates declined by 21%, from 7.8% to 6.2%. Had demographic factors in 2004 been what they were in 1989, the 2004 rates would have been almost identical. Changes in multiple births accounted for only 16% of the increase in medically induced rates. Our analysis suggests that the increase in preterm births is more likely to be due primarily to changes in obstetric practice...

## The impact of sex ratio and economic status on local birth rates

Chipman, A.; Morrison, E.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.09%
Human mating and reproductive behaviour can vary depending on various mechanisms, including the local sex ratio. Previous research shows that as sex ratios become female-biased, women from economically deprived areas are less likely to delay reproductive opportunities to wait for a high-investing mate but instead begin their reproductive careers sooner. Here, we show that the local sex ratio also has an impact on female fertility schedules. At young ages, a female-biased ratio is associated with higher birth rates in the poorest areas, whereas the opposite is true for the richest areas. At older ages, a female-biased ratio is associated with higher birth rates in the richest, but not the poorest areas. These patterns suggest that female–female competition encourages poorer women to adopt a fast life-history strategy and give birth early, and richer women to adopt a slow life-history strategy and delay reproduction.

## Exploration of Preterm Birth Rates Using the Public Health Exposome Database and Computational Analysis Methods

Kershenbaum, Anne D.; Langston, Michael A.; Levine, Robert S.; Saxton, Arnold M.; Oyana, Tonny J.; Kilbourne, Barbara J.; Rogers, Gary L.; Gittner, Lisaann S.; Baktash, Suzanne H.; Matthews-Juarez, Patricia; Juarez, Paul D.
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.1%
Recent advances in informatics technology has made it possible to integrate, manipulate, and analyze variables from a wide range of scientific disciplines allowing for the examination of complex social problems such as health disparities. This study used 589 county-level variables to identify and compare geographical variation of high and low preterm birth rates. Data were collected from a number of publically available sources, bringing together natality outcomes with attributes of the natural, built, social, and policy environments. Singleton early premature county birth rate, in counties with population size over 100,000 persons provided the dependent variable. Graph theoretical techniques were used to identify a wide range of predictor variables from various domains, including black proportion, obesity and diabetes, sexually transmitted infection rates, mother’s age, income, marriage rates, pollution and temperature among others. Dense subgraphs (paracliques) representing groups of highly correlated variables were resolved into latent factors, which were then used to build a regression model explaining prematurity (R-squared = 76.7%). Two lists of counties with large positive and large negative residuals, indicating unusual prematurity rates given their circumstances...

## Month of Birth and Children’s Health in India

Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
46.06%
The authors use data from three waves of the India National Family Health Survey to explore the relationship between the month of birth and the health outcomes of young children in India. They find that children born during the monsoon months have lower anthropometric scores compared with children born during the fall and winter months. The authors propose and test four hypotheses that could explain such a correlation. The results emphasize the importance of seasonal variations in affecting environmental conditions at the time of birth and determining the health outcomes of young children in India. Policy interventions that affect these conditions could effectively impact the health and achievement of these children, in a manner similar to nutrition and micronutrient supplementation programs.

## Trends in age- and parity-specific fertility in Australia

Kippen, Rebecca
Tipo: Conference paper Formato: 137717 bytes; 86240 bytes; 356 bytes; 614 bytes; 356 bytes; 357 bytes; 100 bytes; 358 bytes; application/pdf; application/pdf; application/octet-stream; application/octet-stream; application/octet-stream; application/octet-stream; application/octet-stream
EN_AU
Relevância na Pesquisa
46.24%
Paper to be presented at the IUSSP Seminar on ‘International Perspectives on Low Fertility: trends, theories and policies’, Tokyo, March 21–23, 2001.; Examination of fertility rates in Australia indicates a fall over time in both period and cohort fertility. Period total fertility has been below replacement level for twenty-five years, while cohorts completing their fertility in the first decade of the 21st century are likely to have around replacement-level fertility. Policy-makers and others in Australia are concerned about the potential for further fertility decline, given the impact this would have on population age structure and growth rates. This paper tests the hypothesis that the recent fall in fertility is due solely to changes in age-specific first-birth rates, resulting from delayed parenthood and increased levels of childlessness. Age- and parity-specific fertility rates for the period 1991–98 are constructed. These show that recent fertility declines are driven by changes in first- and second-birth rates, rather than first-birth rates only, while rates for higher order births remain relatively constant. One implication of this is the increasing prevalence of childlessness and one-child families in Australia. The author uses the 1991–98 age- and parity-specific fertility rates as the basis of four different projections of fertility. The likelihood of each of these projections given past trends in fertility is considered.; no

## Paternal body mass index is associated with decreased blastocyst development and reduced live birth rates following assisted reproductive technology

Bakos, H.; Henshaw, R.; Mitchell, M.; Lane, M.
Fonte: Elsevier Science Inc Publicador: Elsevier Science Inc
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.15%
OBJECTIVE: To determine the relationship between paternal body mass index (BMI), embryo development and pregnancy, and live birth outcomes after assisted reproductive technology (ART). DESIGN: Retrospective analysis of ART cycles. SETTING: Major assisted reproduction center. PATIENT(S): Three hundred five couples undergoing ART in a private fertility clinic. INTERVENTION(S): No intervention was undertaken in patients involved in this study. MAIN OUTCOME MEASURE(S): Live birth outcomes and clinical pregnancy rates. RESULT(S): No significant relationship between paternal BMI and early embryo development was found. However, increased paternal BMI was associated with decreased blastocyst development, clinical pregnancy rates and live birth outcomes. CONCLUSION(S): To our knowledge, this is the first report linking increased paternal BMI and clinical pregnancy and live birth rates after ART treatment. Further work to elucidate the mechanisms involved is required.; Hassan W. Bakos, Richard C. Henshaw, Megan Mitchell and Michelle Lane

## Single blastocyst embryo transfer maintains comparable pregnancy rates to double cleavage-stage embryo transfer but results in healthier pregnancy outcomes

Zander-Fox, D.; Tremellen, K.; Lane, M.
Fonte: Blackwell Publishing Asia Publicador: Blackwell Publishing Asia
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.1%
Background: The optimal outcome after IVF is a live, healthy, singleton term baby. This can be achieved by transferring a single embryo, but at the possible expense of reducing pregnancy rates. Recent studies suggest that delaying transfer of embryos to the blastocyst stage (day 4 ⁄ 5), rather than the more traditional cleavage stage (day 2–3), allows for better selection of the best embryo, maximising pregnancy rates from a single embryo transfer (SET). The aim of this study was to assess pregnancy outcomes in relation to changing embryo transfer practices. Methods: A retrospective analysis of pregnancy outcomes was made between IVF cycles conducted in 2007 when blastocyst SET became standard practice, with IVF cycles in 2003 when double cleavage-stage embryo transfer was the norm. Results: The implementation of a blastocyst SET policy resulted in a significant decrease in multiple birth rates, while maintaining live birth delivery rate comparable to double cleavage-stage transfer (27.2% versus 24.8%, respectively, N.S.). Conclusion: Improvements in culturing protocols have facilitated extended culture, increasing embryo selection capability. These results indicate that it is now possible to maintain excellent pregnancy rates with SET blastocyst culture...

## Acupuncture to improve live birth rates for women undergoing in vitro fertilization: a protocol for a randomized controlled trial

Smith, C.; De Lacey, S.; Chapman, M.; Ratcliffe, J.; Norman, R.; Johnson, N.; Sacks, G.; Lyttleton, J.; Boothroyd, C.
Fonte: BioMed Central Ltd. Publicador: BioMed Central Ltd.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
56.06%
BACKGROUND: IVF is a costly treatment option for women, their partners, and the public. Therefore new therapies that improve reproductive and health outcomes are highly desirable. There is a growing body of research evaluating the effect of acupuncture administered during IVF, and specifically on the day of embryo transfer (ET). Many trials are heterogeneous and results inconsistent. There remains insufficient evidence to determine if acupuncture can enhance live birth rates when used as an adjunct to IVF treatment. The study will determine the clinical effectiveness of acupuncture with improving the proportion of women undergoing IVF having live births. Other objectives include: determination of the cost effectiveness of IVF with acupuncture; and examination of the personal and social context of acupuncture in IVF patients, and examining the reasons why the acupuncture may or may not have worked. METHODS: We will conduct a randomized controlled trial of acupuncture compared to placebo acupuncture. Inclusion criteria include: women aged less than 43 years; undergoing a fresh IVF or ICSI cycle; and restricted to women with the potential for a lower live birth rate defined as two or more previous unsuccessful ETs; and unsuccessful clinical pregnancies of quality embryos deemed by the embryologist to have been suitable for freezing by standard criteria. Women will be randomized to acupuncture or placebo acupuncture. Treatment is administered on days 6 to 8 of the stimulated cycle and two treatments on the day of ET. A non-randomized cohort of women not using acupuncture will be recruited to the study. The primary study outcome is the proportion of women reporting a live birth. Secondary outcomes include the proportion of women reporting a clinical pregnancy miscarriage prior to 12 weeks...

## On the Contribution of Demographic Change to Aggregate Poverty Measures for the Developing World

Ravallion, Martin
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH
Relevância na Pesquisa
46.17%

## Validity of pre and post-term birth rates based on the date of last menstrual period compared to early obstetric ultrasonography

Medeiros,Maria Nilza Lima; Cavalcante,Nádia Carenina Nunes; Mesquita,Fabrício José Alencar; Batista,Rosângela Lucena Fernandes; Simões,Vanda Maria Ferreira; Cavalli,Ricardo de Carvalho; Cardoso,Viviane Cunha; Bettiol,Heloisa; Barbieri,Marco Antonio;
Fonte: Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz Publicador: Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz
Tipo: Artigo de Revista Científica Formato: text/html