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1.
A rapid decline in fertility took place in Suriname between 1962 and 1974, and then stopped. While this sudden stabilization is surprising, it is not unusual. Similar trends have occurred in some Caribbean and Latin American countries. This article analyzes the post-1960 trend in fertility in Suriname and seeks to determine whether the 1962-74 fertility decline resulted from changes in socioeconomic conditions or was caused by the activities of the Suriname Family Planning Association. The measures used are the general fertility rate, the total fertility rate by ethnic group as well as by 5-year age groups, and gross and net reproduction rates by ethnic group. All the measures point to a rapid continuing decline of fertility between 1962 and 1974, followed by a rise. The data suggest that major socioeconomic changes had already been under way for some years, when fertility started to fall in 1962. The Suriname Family Planning Association was not founded until 1968, which implies that the organization did not start the decrease. However, once the organization was founded, it continually expanded its activities and made an obvious contribution to the use of contraceptives that increased significantly in the 1970s. It is concluded that the drop in fertility resulted from the process of modernization along with the rapid increase in the use of contraceptives.  相似文献   

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Free access to contraception and effective legislation measures, have resulted in a decline in fertility in Singapore. A new population policy of 'three children or more if you can afford it' was therefore introduced in 1986. This paper discusses the new population policies and measures their effect on fertility in Singapore.  相似文献   

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Recent trends and patterns in fertility in Australia   总被引:1,自引:0,他引:1  
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Recent data from Bangladesh reveal evidence of some fertility decline. Although fertility increased among younger age groups between 1975 and 1983, it was offset by a decrease in fertility in the older age groups, resulting in a slight overall decrease in total fertility in 1983. Fertility was lower among urban residents, educated mothers and contraceptive users than among rural residents, uneducated mothers and contraceptive non-users, respectively, particularly in 1983.  相似文献   

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The objectives of this article are, first, to provide improved estimates of recent fertility levels and trends in Nepal and, second, to analyse the components of fertility change. The analysis is based on data from Nepal's 1996 and 2001 Demographic and Health Surveys. Total fertility rates (TFR) are derived by the own-children method. They incorporate additional adjustments to compensate for displacement of births, and they are compared with estimates derived by the birth-history method. Fertility is estimated not only for the whole country but also by urban/rural residence and by woman's education. The own-children estimates for the whole country indicate that the TFR declined from 4.96 to 4.69 births per woman between the 3-year period preceding the 1996 survey and the 3-year period preceding the 2001 survey. About three-quarters of the decline stems from reductions in age-specific marital fertility rates and about one-quarter from changes in age-specific proportions currently married. Further decomposition of the decline in marital fertility, as measured by births per currently married woman during the 5-year period before each survey, indicates that almost half of the decline in marital fertility is accounted for by changes in population composition by ecological region, development region, urban/rural residence, education, age at first cohabitation with husband, time elapsed since first cohabitation, number of living children at the start of the 5-year period and media exposure. With these variables controlled, another one-third of the decline is accounted for by increase in the proportion sterilized at the start of the 5-year period before each survey.  相似文献   

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Canada’s eastern Arctic (Nunavut and Arctic Quebec—Nunavik, N of 60°) supports large numbers of seabirds in summer. Seabird breeding habitat in this region includes steep, rocky coasts and low-lying coasts backed by lowland sedge-meadow tundra. The former areas support colonial cliff- and scree-nesting seabirds, such as murres and fulmars; the latter inland or coastal seabirds, such as terns, gulls and jaegers. The region supports some 4 million breeding seabirds, of which the most numerous are thick-billed murres (Uria lomvia; 75%), black guillemots (Cepphus grylle; 9%), northern fulmars (Fulmarus glacialis; 8%) and black-legged kittiwakes (Rissa tridactyla; 6%). The majority of Arctic seabirds breed in a small number of very large colonies (>10,000 birds), but there are also substantial numbers of non-colonial or small-colony breeding populations that are scattered more widely (e.g. terns, guillemots). Population trends among Canadian Arctic seabirds over the past few decades have been variable, with no strongly negative trends except for the rare ivory gull (Pagophila eburnea): this contrasts with nearby Greenland, where several species have shown steep declines. Although current seabird trends raise only small cause for concern, climate amelioration may enable increased development activities in the north, potentially posing threats to some seabirds on their breeding grounds.  相似文献   

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Premarital fertility, defined as fertility before first marriage, was found to be highly prevalent in Namibia. According to data from the 1992 and 2000 DHS surveys, the proportion of premarital births was 43% for all births, and 60% for the first birth. This seemed to be primarily due to a late mean age at first marriage (26.4 years) and low levels of contraception before first marriage. Data were analysed using a variety of demographic methods, including multiple decrement life table and multivariate logistic models. Major variations were found by ethno-linguistic groups: Herero and Nama/Damara had the highest levels of premarital fertility (above 60%); Ovambo and Lozi had intermediate levels of premarital fertility (around 40%); Kavongo and San appeared to have kept a more traditional behaviour of early marriage and low levels of premarital fertility (around 20%). The largest ethno-linguistic group, the Ovambo, were in a special situation, with fast increasing age at marriage and average level of premarital fertility. Whites and mixed races also differed, with Afrikaans-speaking groups having a behaviour closer to the average, whereas other Europeans had less premarital fertility despite an average age at marriage. Ethnic differences remained stable after controlling for various socioeconomic factors, such as urbanization, level of education, wealth, access to mass media, and religion. Results are discussed in light of the population dynamics and political history of Namibia in the 20th century.  相似文献   

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K. S. Lee  L. M. Gartner  N. Paneth  L. Tyler 《CMAJ》1982,126(4):373-376
In Canada between 1958 and 1977 the neonatal mortality dropped by more than 50%. the decline was most prominent from 1963 and was almost entirely due to an improvement in neonatal birthweight-specific mortality, which suggests an improvement in perinatal medical care. The timing and pattern of the decline are similar to those reported for the United States. There was a transient increase in the incidence of low and very low birthweight in both countries in the late 1960s. The cause of this increase remains unexplained.  相似文献   

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In 2004 the first livebirth after cryopreserved ovarian tissue transplantation has been reported which is a turning point in fertility preservation after anticancer treatment and a result of almost 50 years of research. However transplantation of cryopreserved ovary is still experimental method and further study needs to be done on the risk of cancer cell reimplantation, this method is very promising for cancer patients who wants to preserve fertility after cancer treatment. This is a review of methods used for cryopreserved ovarian tissue.  相似文献   

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Celia Rodd  Atul K. Sharma 《CMAJ》2016,188(13):E313-E320
Background:Previous studies have shown an increase in the prevalence of overweight and obesity among Canadian children from 23.3% to 34.7% during 1978–2004. We examined the most recent trends by applying current definitions of overweight and obesity based on World Health Organization (WHO) body mass index (BMI) thresholds and recently validated norms for waist circumference and waist:height ratio.Methods:We examined directly measured height and weight data from the Canadian Community Health Survey (2004–2005) and the Canadian Health Measures Survey (2009–2013). We calculated z scores for BMI, height and weight based on the 2014 WHO growth charts for Canada, including the new extension of weight-for-age beyond 10 years. To calculate z scores for waist circumference and waist:height ratios, we used new charts from the reference population in the US NHANES III (National Health and Nutrition Examination Survey, 1988–1994).Results:Data were available for 14 014 children aged 3–19 years for the period 2004–2013. We observed a decline in the prevalence of overweight or obesity, from 30.7% (95% confidence interval [CI] 29.7% to 31.6%) to 27.0% (95% CI 25.3% to 28.7%) (p < 0.001) and stabilization in the prevalence of obesity at about 13%. These trends persisted after we adjusted for age, sex and race/ethnicity. Although they declined, the median z scores for BMI, weight and height were positive and higher than those in the WHO reference population. The z scores for waist circumference and waist:height ratio were negative, which indicated that the Canadian children had less central adiposity than American children in historic or contemporary NHANES cohorts.Interpretation:After a period of dramatic growth, BMI z scores and the prevalence of overweight or obesity among Canadian children decreased from 2004 to 2013, which attests to progress against this important public health challenge.Ongoing pan-Canadian surveys such as the Canadian Community Health Survey (CCHS) and Canadian Health Measures Survey (CHMS) are important to evaluate the health of our population using representative national samples.1,2 Self-reported heights and weights replaced direct measurement during 1978–2004, which underestimated true rates of overweight and obesity.3 A subsequent comparison of directly measured heights and weights during the same period showed an alarming increase in the prevalence of overweight or obesity among Canadian children aged 2–17 years, from 23.3% (95% confidence interval [CI] 20.5% to 26.0%) to 34.7% (95% CI 33.0% to 36.4%) based on the new World Health Organization (WHO) definitions.1In Canada, the definitions of overweight and obesity changed with the introduction of the 2010 WHO growth charts for Canada.4,5 Previous definitions were based on body mass index (BMI) percentiles from the 2000 US Centers for Disease Control and Prevention (CDC) growth charts.6 In addition to revising these percentile thresholds, the WHO charts were based on a different reference population; as a result, the proportion of Canadian children classified as overweight or obese increased with the introduction of the new WHO charts.1,7,8 Moreover, the absolute percentile thresholds now vary by age, with toddlers (2 to ≤ 5 yr) having higher thresholds to define overweight and obesity than older children (age > 5 to 19 yr).4Results from the United States have shown a decline in obesity rates among toddlers and a plateau in rates among older children;9,10 stabilization has also been noted in other jurisdictions (e.g., Germany and Australia).1116 We undertook this study to determine the most recent trends in the prevalence of overweight and obesity among Canadian children using the current WHO weight charts for Canada applied to a representative sample of children.  相似文献   

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