Showing papers on "Fertility published in 1997"
01 May 1997
TL;DR: It appears that the prevalence of pelvic inflammatory disease (PID) and vaginal douching have both decreased since 1988, and the proportion of teenagers who have ever had sexual intercourse decreased slightly between 1990 and 1995.
Abstract: This report presents data on wide range of topics from the 1995 National Survey of Family Growth including: pregnancy and birth marriage divorce cohabitation sexual intercourse contraception infertility use of family planning and other conditions and behavior. The data reported are based on in-person interviews with a national sample of 10847 women 15-44 years of age. The interviews lasted an average of 103 minutes. The response rate was 79% and the sample data are adjusted for nonresponse and are national estimates. Following large increases in the 1970s and 1980s the proportion of teenagers who have ever had sexual intercourse decreased slightly between 1990 and 1995; condom use both at first intercourse and currently has increased markedly since the 1970s. These changes may have contributed to the decrease in teen birth rate observed in the 1990s. For all women 15-44 years of age the number whose partner was currently using the condom (at the date of the interview) increased from 3.6 million in 1982 to 5.1 million in 1988 and to 7.9 million in 1995. About 8% of women reported that their first intercourse was not voluntary. This result is consistent with an earlier national survey. Furthermore about 20% reported that they have been forced by a man to have intercourse at some time in their lives. About 10% of births in 1990-95 were unwanted by the mother compared with 12% in 1984-88. The decrease of unwanted birth was particularly high for Black women.
859 citations
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TL;DR: Men's role in reproduction has gained in prominence but demographic research has focused on a problem-oriented view and limited topics as discussed by the authors, and men should be studied as womens partners and as individuals with distinct interesting reproductive histories.
Abstract: This paper aimed to explain why men have been excluded from demographic research and the new interest in studying mens roles; to evaluate existing research on men; and to suggest future research directions. Mens role in reproduction has gained in prominence but demographic research has focused on a problem-oriented view and limited topics. Men should be studied as womens partners and as individuals with distinct interesting reproductive histories. Barriers to inclusion of men in demographic research include norms of the US White middle class for demographic theorizing about fertility. Demographers view men in their economic roles and devalue their role in fertility except as providers of sperm and barriers to contraceptive use. The Western family norm assumes agreement between mens and womens marital interests and the isolated unsupported role of mother. Recent theories are addressing issues of power and negotiation within partner relations. Cultural evidence challenges prior norms. A male sample presents methodological problems. Feminism and the womens health movement have shifted the focus to men. Classic demographic transition theory has failed to explain fertility change in a range of settings. Methods from other disciplines and the inclusion of qualitative data open up research options for studying men. A broader contextual analysis is gaining in popularity. Two demographic trends will require future research on mens role in family planning and fertility: the relaxation of links between marriage and childbearing and cumulative widening gaps between the reproductive experiences of men and women.
476 citations
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TL;DR: It is suggested that the crisis in the authors' understanding of fertility transitions is more apparent than real and an interactive approach to explaining fertility transitions that is closely allied to existing theories but focuses on conditions that lead couples to switch from postnatal to prenatal controls on family size is suggested.
Abstract: In this essay. I suggest that the crisis in our understanding of fertility transitions is more apparent than real. Although most existing theories of fertility transition have been partially or wholly discredited, this reflects a tendency to assume that all fertility transitions share one or two causes, to ignore mortality decline as a precondition for fertility decline, to assume that pretransitional fertility is wholly governed by social constraints rather than by individual decision-making. and to test ideas on a decadal time scale. I end the essay by suggesting a perceptual. interactive approach to explaining fertility transitions that is closely allied to existing theories but focuses on conditions that lead couples to switch from postnatal to prenatal controls on family size.
456 citations
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TL;DR: In this article, the authors evaluated the impact of these policies on the quality of life of families, and even fewer have evaluated their impact on the demographic, while such policies have been welcomed by the electorate, we know very little about their actual effect.
Abstract: quality of life of families, either financially or by allowing parents to combine more easily employment and family responsibilities. But while such policies have been welcomed by the electorate, we know very little about their actual effect. Few studies have evaluated the impact of these policies on the quality of life of families, and even fewer have evaluated their impact on the demographic
430 citations
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TL;DR: In this article, the authors examined the relationship between fertility decline in India and the evidence of an increase in sex bias and found that fertility decline led to a reduction in excess mortality of adult females.
Abstract: This study examines the relationship between fertility decline in India and the evidence of an increase in sex bias. Data were obtained from the 1981 and 1991 Registrar General of India and from Khanna re-study villages in the Punjab (moderate-fertility population) and in Kerala (low-fertility population) in 1991. Total fertility declined by 20% during 1981-91. The number of sons desired by women who were childless declined by only 7.4%. Among the Khanna sample reduced fertility led to a decline in excess mortality of women from 9% to zero when the sex bias was unchanged and fertility level varied. When fertility was kept constant at a low level and the sex bias varied excess mortality of women increased from zero to 25%. The findings suggest that changes in birth distribution by parity outweigh intensified sex bias at lower parities. The sex ratios of children during 1981-91 rose in all states including the south where the sex ratio has generally been more balanced. Data indicate that over a million additional girls aged 0-6 years were missing during 1981-91. Declining fertility led to a reduction in excess mortality of adult females. The sex ratios of age-specific deaths remained constant during 1979-81 and 1990-91. The author estimates how much the sex ratio of children can be attributed to sex-selective abortions. During 1981-91 about 4.2 million excess postnatal deaths occurred among girls or 4 excess postnatal deaths for each excess prenatal death among girls (1 million aborted female fetuses). This suggests that sex-selective abortion accounted for the missing girls. The sharpest rise in the sex ratio at birth with parity was in Punjab for 1990-91. The model of the relationship between the decline in total fertility in each major state with a change in the sex ratios of children during 1981-91 indicated that the sex ratio increased more in northern states with less fertility decline.
373 citations
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TL;DR: No relation was found between age at menarche and age at natural menopause and Frisch's hypothesis could not be corroborated at the individual level, and it is suggested that age at Menarches and Menopause should be treated as independent risk factors for breast cancer.
331 citations
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TL;DR: The question is whether the outcome under investigation (discharge from a psychiatric hospital with a diagnosis of schizophrenia in the Netherlands) is possibly associated with higher socioeconomic status of origin, because only this would lead to a spurious association.
Abstract: If an event like the Dutch Hunger Winter caused a unique and dramatic decline in population fertility that differentially affected the social classes, confounding by socioeconomic status must be ruled out before conclusions can be drawn about a possible association between prenatal nutritional deficiency and later schizophrenia, as suggested by Susser et al1The exposed (EX2) cohort was marked by a 50% decline in fertility This decrease was associated with socioeconomic status, because it particularly affected the class of manual occupations2The authors state that "no relation has been found in the Netherlands between schizophrenia and low social class of origin" The question, however, is whether the outcome under investigation (discharge from a psychiatric hospital with a diagnosis of schizophrenia in the Netherlands) is possibly associated with higher socioeconomic status of origin, because only this would lead to a spurious association In fact, the well-known Dutch study3
268 citations
01 Dec 1997
TL;DR: The 1996-97 Demographic and Health Survey in Bangladesh as discussed by the authors showed that fertility was about 60% higher in rural areas than urban areas and women with no education had higher fertility compared to women with at least some secondary education.
Abstract: This report presents the full findings of the 1996-97 Demographic and Health Survey in Bangladesh. Findings were based on a nationally representative sample of 9127 ever married women aged 10-49 years and 3312 currently married men aged 15-59 years. Information is provided on introductory backgrounds of government policies government programs and research methods; household and respondent characteristics; fertility and fertility regulation; proximate determinants; fertility preferences; infant and child mortality; maternal and child health; infant feeding childhood and maternal nutrition; knowledge of AIDS; and availability of health and family planning services. Appendices include among other items the questionnaire. Findings indicate that fertility declined only slightly from 1991-93 to 1994-96 from 3.3 to 3.4 births/woman. Fertility was much higher in Sylhet and Chittagong Divisions and much lower in Rajshahi and Khulna Divisions. Fertility was about 60% higher in rural areas. Fertility was higher among women with no education (3.9) compared to women with at least some secondary education (2.1). The data confirm that couples now accept a small family norm. 60% of ever married women preferred a 2-child family. An additional 20% desired 3 children. The percentage of women with 2 children who wanted no more children increased from 39% to 50% between 1991 and 1996-97. About 33% of births in the preceding 3 years were unplanned 20% were mistimed and 11% were unwanted. Modern method use among married women increased to 42%. There was a shift away from permanent methods.
256 citations
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30 Sep 1997
TL;DR: Since fertility preservation is becoming more practical for both men and women, producing patient and professional educational materials and developing professional practice guidelines should be high priorities for oncology societies.
Abstract: As more people achieve long-term survival after cancer, sexual dysfunction and infertility have increasingly been recognized as negative consequences that impact quality of life. Sexual dysfunction is a frequent long-term side effect of cancer treatment, but damage to different underlying physiological systems is salient in men versus women. Men frequently have erectile dysfunction (ED) related to damage to the autonomic nervous system and/or reduced circulation of blood to the penis. Hormonal impairment of sexual function is less common. Women, in contrast, are able to overcome damage to autonomic nerves if genital tissues remain structurally intact and estrogenized. Female sexual dysfunction is frequently associated with sudden premature ovarian failure or direct effects of radiation fibrosis or scar tissue causing pain with sexual activity. The lack of validated interventions for sexual rehabilitation after cancer is a major problem, as is finding cost-effective ways of providing services. Concerns about fertility are also a major source of distress to people treated for cancer during childhood or young adulthood, yet many young survivors do not recall any discussion about future childbearing potential with their oncology team. Since fertility preservation is becoming more practical for both men and women, producing patient and professional educational materials and developing professional practice guidelines should be high priorities for oncology societies.
237 citations
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TL;DR: Caldwell's "wealth flows" theory as discussed by the authors suggests that high fertility has been economically advantageous "to most families over most of human history," because children created "wealth" (broadly defined to include "all the money, goods, services and guarantees that one person provides to another"), and that wealth flows were directed upward from the younger to the older generation.
Abstract: FOR THE PAST HALF-CENTURY, demographers have been preoccupied with the issue of fertility reduction. In his influential book, Theory of Fertility Decline, Caldwell (1982: 350) asserted that "[t]he fundamental challenge in the demographic field is to explain the onset of fertility decline." The basic premise of Caldwell's "wealth flows' theory is that high fertility has been economically advantageous "to most families over most of human history,' because children created "wealth' (broadly defined to include "all the money, goods, services and guarantees that one person provides to another"), and that "wealth flows' were directed upward from the younger to the older generation (ibid.: 334, 333). He concluded that " [t]he onset of
229 citations
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TL;DR: The unfavourable correlation between milk yield and health and fertility traits, plus the economic importance of the latter, suggests that future breeding goals should be expanded to include some health disorders and fertility.
Abstract: The purpose of this study was to estimate genetic parameters for measures of fertility and several health disorders in dairy cows. Data consisted of 33732 records, of which 9163 were on heifers, on 305-day milk yield, health disorders and inseminations. Measures of fertility were calculated from calving and insemination dates and included calving interval, days to first service and conception to first service. Health disorders included milk fever, mastitis and lameness. Genetic and phenotypic (co)variances were estimated using restricted maximum likelihood. Heritability estimates for both health disorders and fertility traits were low, ranging from 0·003 to 0·080. All genetic correlations between 305-day milk yield and health and fertility traits, in cows and heifers together, were antagonistic implying that selection for milk yield may have caused a deterioration in health and fertility. The unfavourable correlation between milk yield and health and fertility traits, plus the economic importance of the latter, suggests that future breeding goals should be expanded to include some health disorders and fertility.
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TL;DR: The principal policy implication from this analysis is that vigorous efforts to reduce unwanted pregnancies through family planning programs and other measures are needed early in the fertility transition because, in their absence, unwanted fertility and abortion rates are likely to rise to high levels.
Abstract: This study analyzes trends in unwanted fertility in 20 developing countries, based on data from the World Fertility Surveys and the Demographic and Health Surveys. Although wanted childbearing almost invariably declines as countries move through the fertility transition, the trend in unwanted fertility was found to have an inverted U shape. During the first half of the transition, unwanted fertility tends to rise, and it does not decline until near the end of the transition. This pattern is attributed to the combined effects of an increase in the duration of exposure to the risk of unwanted pregnancy and a rise in contraceptive use as desired family size declines. The substantial variation in unwanted fertility among countries at the same transition stage is caused by variation in the degree of implementation of preferences, the effectiveness of contraceptive use, the rate of induced abortion, and other proximate determinants, such as age at marriage, duration of breastfeeding, and frequency of sexual relations. The principal policy implication from this analysis is that vigorous efforts to reduce unwanted pregnancies through family planning programs and other measures are needed early in the fertility transition because, in their absence, unwanted fertility and abortion rates are likely to rise to high levels.
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TL;DR: In this paper, the authors describe the intellectual development and the empirical implications of the literature on the economics of fertility as it applies to fertility behavior in developed economies and discuss various solutions to the fundamental identification problems that arise in assessing the impact of prices and income on both lifetime and lifecycle fertility behavior.
Abstract: Publisher Summary This chapter describes the intellectual development and the empirical implications of the literature on the economics of fertility as it applies to fertility behavior in developed economies The chapter reviews the literature on dynamic models of fertility behavior over the parents' life cycle, and outlines the ways in which these models extend the static models and the implications that they provide for dimensions of fertility behavior The chapter also discusses various solutions to the fundamental identification problems that arise in assessing the impact of prices and income on both lifetime and lifecycle fertility behavior The theory and econometric methods are better developed than the empirical literature The challenge is to find plausibly exogenous variation in proxies for the price and income concepts appearing in the theories The chapter provides a taxonomy of possible identifying information and gives hope that additional progress can be made in advancing the empirical understanding of fertility behavior
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TL;DR: A study of two generations of Punjabi women in New Delhi found that women's schooling and autonomy as factors in fertility change in Pakistan as mentioned in this paper, and the changing impact of schooling on female autonomy and fertility in an Indian Village.
Abstract: Schooling as Contraception? - Roger Jeffery and Alaka M Basu Girls' Schooling, Autonomy and Fertility Change - Alaka M Basu What Do These Words Mean in South Asia? Maternal Schooling and Fertility - John Cleland and Shireen Jejeebhoy Evidence from Censuses and Surveys Educational Attainment, Status Production and Women's Autonomy - Karuna Chanana A Study of Two Generations of Punjabi Women in New Delhi Women's Schooling and Autonomy as Factors in Fertility Change in Pakistan - Zeba A Sathar Some Empirical Evidence What's the Benefit of Being Educated? Girls' Schooling, Women's Autonomy and Fertility Outcomes in Bijnor - Patricia Jeffery and Roger Jeffery Female Education and Fertility in Bangladesh - Sajeda Amin The Influence of Marriage and the Family Links between Fertility Regulation and the Schooling and Autonomy of Women in Bangladesh - John Cleland, Nashid Kamal and Andrew Sloggett Against the Odds - Carol Vlassoff The Changing Impact of Schooling on Female Autonomy and Fertility in an Indian Village Regional Variations in Female Autonomy and Fertility and Contraception in India - Leela Visaria Female Autonomy and Reproductive Behaviour in Kerala - S Irudaya Rajan, Mala Ramanathan and U S Mishra New Evidence from the Recent Kerala Fertility Survey Female Education, Autonomy and Fertility in Sri Lanka - Bruce Caldwell
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TL;DR: The trend toward postponed childbearing has occurred primarily among women with at least a high school education, particularly among women of childbearing age with 12 or more years of education.
Abstract: Objectives. Advanced maternal age at first birth, but not at subsequent births, may have detrimental health implications for both mother and child, such as a poor birth outcome and an increased risk of maternal breast cancer. However, positive outcomes may also result such as an improvement in economic measures and offspring's performance on cognitive tests. Research has indicated that women increasingly are delaying their first births beyond the early twenties, but the recent trends in socioeconomic disparity in age at first birth, and the implications for public health, have not been well described. Method. This study used national birth certificate data for 1969–1994 to examine age at first birth by maternal education level. Current Population Survey data were also used to examine changes over time in age and educational distribution among women of childbearing age. Results. Age at first birth increased during the time period. Median age at first birth increased from 21.3 to 24.4 between 1969 and 1994, and the proportion of first-time mothers who were age 30 or older increased from 4.1% to 21.2%. Age at first birth increased rapidly among women with 12 or more years of education; nearly half (45.5%) of college graduate women who had their first birth in 1994 were age 30 or older, compared with 10.2% in 1969. However, little change was observed among women with fewer than 12 years of education; among those with 9–11 years of education, only 2.5% of first births in 1994 occurred at age 30 or older. Conclusions. The trend toward postponed childbearing has occurred primarily among women with at least a high school education. Health services use, such as infertility treatment and cesarean section, may increase as a result of delayed childbearing among higher educated women. Future examinations of the association between maternal age at first birth and health outcomes may need to take greater account of socioeconomic differentials.
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TL;DR: The author discusses how she and her husband are concerned about the future of their fertility and the challenges they are facing in trying to find a solution to this problem.
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TL;DR: A simple re-analysis of Szreter’s own data suggests that social class does explain cross-sectional differences in English marital fertility in 1911.
Abstract: Simon Szreter’s book Fertility, Class, and Gender in Britain, 1860-1940 argues that social and economic class fails to explain the cross-sectional differences in marital fertility as reported in the 1911 census of England and Wales. Szreter’s conclusion made the book immediately influential, and it remains so. This finding matters a great deal for debates about the causes of the European fertility decline of the nineteenth and twentieth centuries. For decades scholars have argued whether the main forces at work were ideational or social and economic. This note reports a simple re-analysis of Szreter’s own data, which suggests that social class does explain cross-sectional differences in English marital fertility in 1911.
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TL;DR: Acute famine exposure in utero appears to have no adverse consequences for a woman's fertility, although the excess perinatal mortality in the second generation is unexplained and should be confirmed by other studies.
Abstract: OBJECTIVES: We hypothesized that if prenatal caloric restriction due to nutritional deprivation had affected development of the organs responsible for producing and regulating female reproductive hormones, a woman's fertility would be impaired. METHODS: Women born in Amsterdam from August 1, 1944, through April 15, 1946, a period encompassing a severe 5-month famine, were identified (n = 700; 85% response rate). Date of birth and vital status of all offspring were ascertained by home interview between 1987 and 1991. Famine exposure was inferred from the mother's date of birth. RESULTS: Of the study participants, 74 (10.6%) had no children. The remainder reported 1334 off-spring (1294 singletons, 20 pairs of twins), of whom 14 were stillborn and 22 died in the first 7 days of life. There was no detectable effect of famine exposure on age at menarche, the proportion having no children, age at first delivery, or family size. An excess of perinatal deaths occurred among offspring of famine-exposed women, part...
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TL;DR: The results show that community members accord great significance to child-bearing, but, they have incorrect knowledge of the causes and appropriate treatment of infertility, which has profound implications for reproductive health and reproductive rights of women in the area.
Abstract: There has been very little documentation of the social meaning given to infertility in many developing countries, including Nigeria, where the prevalence of infertility is known to be high. We have conducted a number of qualitative studies aimed at exploring socio-cultural issues associated with infertility in Ile-Ife, Southwestern Nigeria. Twenty-five focus-group discussions were held with knowledgeable persons in the rural and urban parts of the community to ascertain their attitudes towards infertility. The results show that community members accord great significance to child-bearing , but, they have incorrect knowledge of the causes and appropriate treatment of infertility. Focus-group participants mentioned several traditional beliefs regarding the causes of infertility from which they derived a variety of traditional and religious methods for its treatment; many affected couples use these methods of treatment, sometimes singly but most often in combination. Orthodox treatments are less often used because of perceptions of the causes of infertility and lack of confidentiality at the treatment centres. Women are more likely to suffer the social consequences of infertility; they suffer physical and mental abuse, neglect, abandonment, economic deprivation and social ostracism as a result of their infertile status. These findings have profound implications for reproductive health and reproductive rights of women in the area. Measures recommended to ameliorate the adverse consequences of infertility in the community include provision of broad reproductive health education and appropriate services; integration of infertility treatment and prevention into primary health care and the traditional system of health care delivery; and programs aimed at the empowerment of women in the area. * This paper was presented at the International Symposium on Health and Reproductive rights organized by the Centre for Advanced Social Science Health held in Lagos, Nigeria in March 1995. It has also been presented at the 4th World Conference on Women held in Beijing, China; at the International Seminar on Reproductive Health organized by the Social Science and Reproductive Network in Ibadan, Nigeria; and more recently at the 15th World Congress on Fertility and Sterility held in Montpelier, France.
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TL;DR: Time to pregnancy can be used to measure the degree of delay in conceiving, across the whole continuum of biological fertility, in either men or women as discussed by the authors, and the distribution of time to pregnancy largely reflects a sorting process as the more fertile couples become progressively less well represented with the passage of time.
Abstract: INTRODUCTION: Growing evidence of reproductive effects associated with occupational and environmental agents has created the need for research with sensitive and well validated methods. There is a complex relation between manifest effects and underlying pathogenic processes. Conceptions will on average tend to be delayed in a population exposed to an agent that causes embryonic damage, an increase in germ cell mutations, or decreased fertility. STUDYING TIME TO PREGNANCY: Time to pregnancy can be used to measure the degree of delay in conceiving, across the whole continuum of biological fertility, in either men or women. The distribution of time to pregnancy largely reflects a sorting process, as the more fertile couples become progressively less well represented with the passage of time. The basic research strategy is comparison of the time to pregnancy within groups defined by their exposures, allowing for potential confounding factors relating not only to the study subject but also to his or her partner. MEASUREMENT AND VALIDITY: Prospective and retrospective methods are available, and each has strengths and weaknesses. Prospective studies have some theoretical advantages, but have unrepresentative populations and problems of feasibility and cost. Retrospective assessment of time to pregnancy is feasible with a short questionnaire, without intruding into sensitive areas of respondents9 lives, with good validity at the group level, and without the necessity of large populations. Potential biases have been identified that can be minimised by careful design and analysis; the principal remaining problem is difficulty in obtaining exposure data retrospectively.
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TL;DR: Results for the total sample and for women showed a significantly elevated odds ratio for self-reported infertility associated with occupational handling of chemotherapeutic drugs prior to onset of infertility.
Abstract: Although infertility has been identified as an effect of chemotherapy for some cancer patients, the association of infertility with occupational exposure has not been investigated. This case-control study investigated the relationship of infertility with occupational handling of chemotherapy drugs by nurses and pharmacy personnel. Data were gathered by questionnaire from 4659 staff at facilities participating in the National Surgical Adjuvant Breast and Bowel Project collaborative clinical trials network of the National Cancer Institute. The 405 subjects reporting infertility were each matched by sex and age with three control subjects and compared for history of chemotherapeutic drug handling. Results for the total sample and for women showed a significantly elevated odds ratio (OR = 1.5; CI = 1.1 to 2.0) for self-reported infertility associated with occupational handling of chemotherapeutic drugs prior to onset of infertility. For men, the odds ratio was similar but not statistically significant. This worker population, with a mean age of 37, is in the prime of reproductive life. Prevention of chemotherapy side effects by use of available protection is preferable to risking infertility.
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TL;DR: The data suggest that sexual dysfunction and infertility represent the major persisting side effects, even years after diagnosis, and the hypothesis that surveillance patients have fewer sexual problems is not upheld in this study.
Abstract: PURPOSEWe assessed the impact of different treatment modalities on sexuality and fertility in long-term survivors of testicular cancer.MATERIALS AND METHODSThe sample consisted of 85 testicular cancer patients, of whom 19 had undergone chemotherapy with retroperitoneal lymph node dissection (RPLND), 15 had received chemotherapy only, 42 had received infradiaphragmatic radiotherapy, and nine had received surveillance therapy. The questionnaire reported sexual function, marital status, and issues related to fertility and childbearing.RESULTSOne fourth to one half reported some type of sexual impairment in each group. The only significant difference was that approximately 70% of men with RPLND reported inability of ejaculation and a greater decline in semen volume, which is expected. The most striking finding is that the rates and nature of sexual dysfunction of surveillance patients were similar to other treatment groups, except for ejaculatory function. The highest rates of infertility distress were observ...
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TL;DR: The results suggest that the lipid and fatty acid compositions of spermatozoa may be important predictors of fertility.
Abstract: Changes in the proportions of the various lipid components in spermatozoa were investigated throughout the reproductive period (24-72 wk of age) of male chickens. Sperm motility and in vivo fertility were also measured, and correlation coefficients with the lipid values were determined. The proportion of total phospholipid (PL) increased to reach a maximum value at 39 wk and decreased significantly thereafter. The relative content of free cholesterol and triacylglycerols showed no change in spermatozoa during aging or in relation to fertility values; free fatty acids and cholesterol esters increased continuously with age. Of the various PL classes, phosphatidylserine and phosphatidylcholine displayed a pattern of changes with age positively and negatively, respectively, in relation to the changes of fertility. The proportion of phosphatidylethanolamine had significantly decreased by the end of the reproductive period. The proportions of C16:0, C18:0, and C18:1 n-9 within the PL of the spermatozoa increased with age, and those of C20:4n-6, C22:4n-6, and C22: 6n-3 decreased. Positive correlations were found between fertility and total PLs, phosphatidylserine, and PL-bound C20:4n-6 and C22:4n-6; a negative correlation was found between fertility and phosphatidylcholine. Motility was positively correlated with the level of PL and negatively with that of free cholesterol; it was also positively correlated with the levels of C22:4n-6 and C22:6n-3 and negatively with those of C16:0, C18:0, and C18: ln-9. The results suggest that the lipid and fatty acid compositions of spermatozoa may be important predictors of fertility.
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TL;DR: In this paper, the economic models for understanding the empirical regularities in fertility in low-income countries are outlined, and the authors suggest that the changing composition of income between labor and non-human capital and between male and female productivity are as important for the decline in fertility as the overall level of national income.
Abstract: Publisher Summary This chapter outlines the economic models for understanding the empirical regularities in fertility in low-income countries Applications of microeconomics to understand the demand for children emphasize several special aspects of children Their cost to parents is affected by the opportunity cost of the time of mothers, who in most societies contribute a disproportionate share of their time to child rearing Demand models predict and empirical studies confirm that increase in women's wages and education have a more negative impact on fertility than do increase in men's wages and education, or, for that matter, than does nonhuman capital income, which is indeed often associated with increased fertility in low-income agricultural settings The changing composition of income between labor and nonhuman capital and between male and female productivity are as important for the decline in fertility as the overall level of national income An increasing number of studies that suggest programs increasing the schooling of women, improving child health and nutrition, and diffusing family planning methods have contributed to the declines in child mortality, fertility, and population growth rates in low-income developing countries
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TL;DR: In-depth interviews revealed that traditional care like healers and spiritual leaders are frequently consulted long before formal health care, which could be a problem in those cases where infertility is caused by infections.
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01 Mar 1997
TL;DR: This report presents in text and tables the findings of the 1996 Nepal Family Life Survey among a nationally representative sample of 8429 ever married women aged 15-49 years, indicating that fertility declined during the mid-1970s to 1994-96 from over 6 births/ woman to 4.6 births/woman.
Abstract: This report presents in text and tables the findings of the 1996 Nepal Family Life Survey among a nationally representative sample of 8429 ever married women aged 15-49 years. A summary of findings indicates that fertility declined during the mid-1970s to 1994-96 from over 6 births/woman to 4.6 births/woman. Fertility ranges from 2.9 births/woman in urban areas to 4.8 births/woman in rural areas. It ranges from 5.6 births/woman in the Mountains to 4.5 and 4.6 births/woman in the Hills and Terai. Fertility is highest in the Mid-western region with 5.5 births/woman and lowest in the Eastern region with 4.1 births/woman. The median age at first marriage rose to 17.1 years among women aged 20-24 years. One-fourth of the women aged 15-19 years was already a mother. Adolescent pregnancy was more common in rural areas. One-fourth of the births occurred within 24 months of a previous birth. The average woman had almost 60% more births than the ideal. Total wanted fertility was 2.9 births/woman. Contraceptive prevalence among currently married women was 29%; 26% for modern methods. 18% relied on sterilization and 5% used injectables. Contraceptive prevalence in urban areas was 50%. 79% of modern method users obtained supplies from a public source. Child mortality declined over the past 10 years to 1 out of 8 children aged under 5 years. Childhood vaccination coverage was about 76% among children aged 12-23 months. Use of health facilities remained low. Most births occurred at home. Breast feeding was universal. 48% of children aged under 3 years were stunted 11% were wasted and 47% were underweight. 15% of mothers who had given birth during the 3 years preceding the survey were at nutritional risk and 25% had a low body mass index score. Maternal mortality accounted for 27% of deaths among women aged 15-49 years or 5 deaths/1000 live births.
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TL;DR: This article examined the effect of reproduction on subsequent survival and fecundity of male Drosophila melanogaster by reversing the reproductive status of individuals part-way through life, finding that early reproduction caused permanent, irreversible damage to both survival and fertility.
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TL;DR: A relatively small group of women has drastically changed the overall national rates of multiple pregnancies and the introduction of new treatments to enhance fertility has probably caused these changes and has also affected the otherwise decreasing trend in infant mortality.
Abstract: Objective: To study trends in multiple pregnancies not explained by changes in maternal age and parity patterns. Design: Trends in population based figures for multiple pregnancies in Denmark studied from complete national records on parity history and vital status. Population: 497 979 Danish women and 803 019 pregnancies, 1980-94. Main outcome measures: National rates of multiple pregnancies, infant mortality, and stillbirths controlled for maternal age and parity. Special emphasis on primiparous women ≥30 years of age, who are most likely to undergo fertility treatment. Results: The national incidence of multiple pregnancies increased 1.7-fold during 1980-94, the increase primarily in1989-94 and almost exclusively in primiparous women aged ≥30 years, for whom the adjusted population based twinning rate increased 2.7-fold and the triplet rate 9.1-fold. During 1989-94, the adjusted yearly increase in multiple pregnancies for these women was 19% (95% confidence interval 16% to 21%) and in dizygotic twin pregnancies 25% (21% to 28%). The proportion of multiple births among infant deaths in primiparous women ≥30 years increased from 11.5% to 26.9% during the study period. The total infant mortality, however, did not increase for these women because of a simultaneous significant decrease in infant mortality among singletons. Conclusions: A relatively small group of women has drastically changed the overall national rates of multiple pregnancies. The introduction of new treatments to enhance fertility has probably caused these changes and has also affected the otherwise decreasing trend in infant mortality. Consequently, the resources, both economical and otherwise, associated with these treatments go well beyond those invested in specific fertility enhancing treatments.
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TL;DR: Semen analyses obtained from 1980-1995 from 689 healthy men volunteering for screening either as potential sperm donors for a donor insemination programme or to participate in five male contraception research studies highlight the invalidity of extrapolating similar findings on sperm output of self-selected volunteers to the general male community or in using such study groups to characterize sperm output in supposedly 'normal' men.
Abstract: Controversial claims, based on a meta-analysis aggregating 61 heterogeneous observational studies, have been made that human sperm output has decreased by 50% over the last six decades and that this trend may be due to global pollution. If true, such effects should be evident in all areas of the globe; however, longitudinal studies within single centres in Europe and America have produced conflicting results and there are no reports from the southern hemisphere. We therefore reviewed semen analyses obtained from 1980-1995 from 689 healthy men volunteering for screening either as potential sperm donors for a donor insemination programme (n = 509) or to participate in five male contraception research studies (studies no. 1-5, n = 180). All were recruited through the Andrology Unit of the Royal Prince Alfred Hospital, Sydney, by the same doctors using standard methods of recruiting, screening and laboratory examination throughout the period 1980-1995. Recruitment was by advertising without regard to marital or fertility status except in two contraceptive efficacy studies (no. 1 and no. 3) where participants had to be in a stable relationship requiring contraception. Analysing the first semen sample individually or when grouped by year of ejaculation, there was no significant difference in sperm concentration over time or between years or according to year of birth. During the second half of this period, 180 consecutive volunteers were recruited by the same doctors and staff for five male contraception studies. The median sperm concentration for studies no. 1 (103 x 10(6) ml) and no. 2 (142 x 10(6) ml) were significantly (P < 0.05) higher than for studies no. 3-5 (84, 67 and 63 x 10(6) ml, respectively) and for potential sperm donors (median 69 x 10(6) ml). The inconsistency of these estimates illustrates the magnitude of bias (up to 100%) in sperm output that may occur in recruiting groups of self-referred volunteers within a single centre. This highlights the invalidity of extrapolating similar findings on sperm output of self-selected volunteers to the general male community or in using such study groups to characterize sperm output in supposedly 'normal' men.