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Showing papers on "Fertility published in 1981"


Journal ArticleDOI
TL;DR: No studies have yet demonstrated that women on oral pills are at increased risk for growth of these tumors, and low-dose contraceptives should not be contraindicated in patients with leiomyomata if they desire to use this form of contraceptive.

1,455 citations




Journal ArticleDOI
TL;DR: Forty male patients aged 17 years and older and attending the routine Sickle cell outpatient clinic at Lagos University Teaching Hospital, Nigeria, were studied to evaluate the fertility potential of men with sickle cell disease, finding striking differences in sperm concentration, total sperm count, motility, and morphology.

187 citations


Journal ArticleDOI
TL;DR: In this paper, a case study using pretransitional England as a case-study assesses long term trends in family organization and associated fertility in a society in which parity-dependent fertility control was for the most part absent.
Abstract: This paper using pretransitional England as a case-study assesses long term trends in family organization and associated fertility in a society in which parity-dependent fertility control was for the most part absent. It also considers the means by which institutions especially those to do with labor organizations and family welfare mediated between trends in real incomes and completed family sizes. The study concludes that the distinctiveness of the English experience stems from the culturally specific nature of the rules of household formation that gave changes in marriage age and incidence a fundamental role in determining the markedly dynamic quality of fertility before the late nineteenth century. It is found that "these household formation rules appear not to have been much altered by the growth of agrarian and industrial capitalism although they did undermine the capacity of the demographic system to act homeostatically." (summary in FRE SPA)

159 citations


Journal ArticleDOI
TL;DR: Controlling for a variety of socio-economic characteristics of currently married women aged 20–49, and using several analytical approaches, the current fertility of migrants was consistently found to be higher than their own earlier fertility and higher than tha...
Abstract: Reflecting a growing concern with high rates of urban growth in less developed countries, increasing attention focuses on the fertility of migrants to such places. The present study explores the relations between fertility, migration, and urbanization, using ‘own children’ data from the 1970 Census of Thailand. Information on ‘own children’ less than one year old is used to approximate fertility levels in the year before the census, and that on ‘own children’ aged 1–4 fertility levels during the four preceding years. Since migration was defined as a move to current residence between 1965 and 1970, the statistics on ‘own children’ less than five years old allow scrutiny of fertility during the period immediately before and after migration. Controlling for a variety of socio-economic characteristics of currently married women aged 20–49, and using several analytical approaches, the current fertility of migrants was consistently found to be higher than their own earlier fertility and higher than tha...

141 citations


Journal ArticleDOI
TL;DR: Infants of hypothyroid mothers may be normal because their hypothalamic-pituitary thyroid axis develops independently from the mother, and normal thyroid function and somatic development is observed.
Abstract: Published data on the influence of hypothyroidism on fertility, gestation, and the offspring are controversial. We studied nine hypothyroid women during 11 pregnancies. Mean serum values f...

130 citations


Journal ArticleDOI
TL;DR: It is concluded that the magnitude of the additive genetic variance in several fertility traits is considerable, despite the generally low heritability values of individual insemination results.

126 citations


Journal ArticleDOI
TL;DR: The determinants of age-specific marital fertility rates in non-contracepting populations are discussed and the physiological link between nutrition and reproduction in women who are chronically malnourished rather than famished are examined.
Abstract: The determinants of age-specific marital fertility rates in non-contracepting populations are discussed and the physiological link between nutrition and reproduction in women who are chronically malnourished rather than famished are examined. Initial attention is directed to menarche and menopause for these set the outer bounds to the time of childbearing. This is followed by a discussion of the determinants of birth interval. Birth interval and its components are of primary concern because if populations are to fit different numbers of births into similar childbearing spans the intervals between these births must vary. There is reason to believe that the age of menarche might be affected by the level of nutrition. In some countries where nutrition has remained inadequate the age of menarche is comparatively high. Like the age at menarche the age at menopause is likely to have had little influence on overall fertility in Europe. The meager evidence available suggests that the mean age at last birth appears to vary little among populations which do not practice birth control. The length of postpartum anovulation the period after a birth when there is no ovulation is a primary determinant of variation in the length of the birth interval. Research in which the direct measurement of the duration of breastfeeding was possible found that breastfeeding was the primary determinant of the length of postpartum amenorrhea. Researchers in Bangladesh and in Guatemala have found a slight negative relation between nutritional status and the duration of postpartum amenorrhea.

120 citations


Journal Article
TL;DR: The recently developed sperm penetration assay (SPA) tests the functional capacity of sperm and was superior to seminal fluid analysis in predicting both fertility and infertility; in the prediction of infertility, the difference was highly significant.

108 citations


Journal ArticleDOI
TL;DR: Average length of last closed birth interval increased with prolonged breastfeeding in all 8 countries, and 1 month of breastfeeding adds an average of 0.4 months to the birth interval, although there was considerable variation among the countries.
Abstract: Paper based on data generated by the World Fertility Survey in 8 countries: Bangladesh Indonesia Sri Lanka Jordan Peru Guyana Colombia and Panama. The authors address the following issues among others: the prevalence and duration of breastfeeding; variations in the duration of breastfeeding among different subgroups classified by age parity womans education etc; the key determinants of breastfeeding; and the effect of breastfeeding on fertility. The large majority of women in all the countries breastfed their last 2 children the number who did not ranging from 2 to 18%. Duration ranged from 9 months (Panama) to 29 months (Bangladesh). Key determinants were womens education place of residence husbands occupation and survival status of the child--consistent for all 8 countries. Women with more education and those living in urban areas breastfeed for shorter periods. Sex of child age and parity of mother and mothers work experience showed no independent effect on duration of breastfeeding. Although breastfeeding is not used for family limitation the possibility that it is used to prolong birth intervals cannot be ruled out. Average length of last closed birth interval increased with prolonged breastfeeding in all 8 countries. 1 month of breastfeeding adds an average of 0.4 months to the birth interval although there was considerable variation among the countries. To what extent these variations may be due to differences in reporting errors or to other factors could not be determined. (Authors modified)

Journal ArticleDOI
TL;DR: As assessed by semen quality the majority of patients were subfertile when first seen, hence, sperm banking may be a poor guarantee for future reproduction in these patients.

Journal ArticleDOI
TL;DR: Mean fertility in three koala populations in Victoria in 1979 varied from 63% on French I, to 13% at Walkerville and 22% on Phillip I, and this is thought to be due to a widespread reproductive tract disease in females.
Abstract: Mean fertility in three koala populations in Victoria in 1979 varied from 63% on French I, to 13% at Walkerville and 22% on Phillip I. Similar differences between the two island populations have existed for at least 30 y. A method of assigning animals to age classes on the basis of the wear patterns on the premolar was devised and reproduction in 1979 examined on an age-specific basis. The low fertility was associated with a reproductive failure among females older than 3 y. On Phillip I. this is thought to be due to a widespread reproductive tract disease in females, possibly caused by ingestion of phytooestrogens from eucalypt foliage. At Walkerville a combination of reproductive tract disease, poor nutrition and heavy tick burdens is thought to be the cause.

McCann Mf, Liskin Ls, Piotrow Pt, Rinehart W, Fox G 
01 Nov 1981
TL;DR: Biological scientists and demographers are unanimous in concluding that although breastfeeding substantially contributes to birth spacing and fertility control in many areas it is an unreliable means of contraception.
Abstract: Studies show that breastfeeding is ideal for infant nutrition and is an important means of spacing births Breast milk provides some immunological protection to the infant protects against infection and malnutrition satisfies the infants nutritional needs and costs less than other feeding substitutes Breastfeeding also protects against pregnancy although the length of the contraceptive effect cannot be predicted Analysis of breastfeeding trends and patterns shows that although most women in developing countries initially breastfeed their children the length of breastfeeding is declining especially in urban areas The practice of breastfeeding in contrast appears to be increasing in some developed countries after several decades of decline Breastfeeding trends and patterns may be influenced by the following sociodemographic factors: 1) urban-rural residence 2) parental education and socioeconomic status 3) mothers age and parity 4) support from family and friends 5) mothers employment and 6) contraceptive use Biological scientists and demographers are unanimous in concluding that although breastfeeding substantially contributes to birth spacing and fertility control in many areas it is an unreliable means of contraception Breastfeeding women are therefore advised to seek alternative means of contraception to avoid pregnancy The effects of hormonal contraception on breastfeeding have not been established but the following points can be made: 1) combined estrogen-progestin oral pills decrease milk volume in some cases 2) progestin-only contraception does not affect milk volume or increase it 3) small doses of hormones used for contraception do not appear to prevent initiation of lactation and 4) minute amounts of hormones are transmitted to the infant in breast milk and although no serious effects have been observed the long-term effects are unknown Determining the appropriate contraception during breastfeeding requires consideration of the womans personal preference availability and convenience of various methods impact on fertility of starting different methods at different times after delivery and possible effects on lactation Implications for family planning programs and research needs are also discussed

Journal ArticleDOI
TL;DR: In this paper, the demographic implications of different trajectories of future fertility demonstrate that a cessation of growth by 2000 would require implausably low fertility and result in extremely unbalanced age distributions.
Abstract: Recently available data confirm reports of a Chinese population of almost a billion with a very low death rate and a birth rate that has been halved in 15 years. Illustrative projections of the demographic implications of different trajectories of future fertility demonstrate that a cessation of growth by 2000 would require implausably low fertility and result in extremely unbalanced age distributions -- neither of which would be acceptable as policy goals. Such projections illustrate the value of demographic research in formulating Chinese population policies. Sparseness of existing Chinese resources in the social sciences and statistics however is a major hindrance to the growth of population science within the country. (Authors) (Summaries in ENG FRE SPA)

01 Jan 1981
TL;DR: There was no difference (P>.05) between groups for the number of mares exhibiting estrus after treatment or follicular activity during or after treatment, but the interval from treatment to estrus was shorter for mares treated during diestrus vs those treated during estrus.
Abstract: On February 4, 14 of 28 seasonally anestrous mares were fed .044 mg per kilogram of body weight of an oral progestin, allyl trenbolone (17a-allyl-estratriene 4-9-11, 17/3-ol-3-one) for 12 days. There was no difference (P>.05) between groups for the number of mares exhibiting estrus after treatment or follicular activity during or after treatment. After March 6, 18 mares that had not yet ovulated were used in a second trial. On day 3 of estrus, nine of 18 mares were a~signed to be fed allyl trenbolone for 12 days. Estrus ceased in all mares within 3 days of treatment. Duration of post-treatment estrus, interval from end of treatment to ovulation and from estrus to ovulation were shorter (P<.01) for treated mares. Influence of stage of cycle at the onset of treatment was evaluated in a third trial. Mares (N = 25) were assigned to one of five groups: 1) controls artificially inseminated every other day (E/O) during estrus; 2) fed allyl trenbolone for 12 days beginning day 3 of estrus and bred E/O; and groups 3 to 5) fed allyl trenbolone for 12 days beginning day 3 of estrus or days 5 or 10 of diestrus. Mares in groups 3, 4 and 5 were given HCG (3,300 IU) on day 17 and inseminated on days 17 and 19. The interval from treatment to estrus was shorter (P<.05) for mares treated during diestrus vs those treated during estrus. Pregnancy rates were not different (P>.IO) among groups

Book
30 Apr 1981
TL;DR: In this paper, the authors present a framework for the analysis of religious fertility differentials in fertility control knowledge, attitudes and practices in the context of Lebanese religious groups and family size preferences.
Abstract: 1. Theoretical framework 2. Data and methodology Data 3. Lebanese religious groups 4. Religious fertility differentials 5. Religious differentials in family size preferences 6. Religious differentials in fertility control knowledge, attitudes and practices 7. Summary and conclusions.

Journal ArticleDOI
TL;DR: It is suggested that advancement in female education can be expected to influence fertility behavior even without simultaneous changes in other factors such as increasing opportunity for participation in the paid labor force in the modem sector.
Abstract: This paper investigates the structure of the relationship between female education and fertility. It is based on data published in First Country Reports of the World Fertility Surveys for eleven countries—Costa Rica, Colombia, Dominican Republic, Panama, Fiji, Korea, Malaysia, Pakistan, Sri Lanka, Thailand, and Indonesia. The cumulative marital fertility of educated women is shown to be similar in different settings. A lack of uniformity in the education and fertility relationship including the curvilinear nature of this relationship observed across countries is shown to be attributable to marked differences between countries in the average fertility of women with no education rather than to the presumed differences in the average fertility of the educated women. The structure of the relationship is shown to be similar across several developing countries. This analysis suggests that advancement in female education can be expected to influence fertility behavior even without simultaneous changes in other factors such as increasing opportunity for participation in the paid labor force in the modem sector.

Journal Article
TL;DR: In the early 60s, there has been a trend to delay 1st births as mentioned in this paper and about 1/3 of 1st birth are now to women of 25 years of age or older.
Abstract: Since the early 60s there has been a trend to delay 1st births. About 1/3 of 1st births are now to women of 25 years of age or older. The decreased risk of unwanted conception and birth has made it easier for couples to delay parenthood. In addition the preference for later parenthood may have increased with the increased education and labor force participation of women. The timing of 1st births affects fertility rates family economies and relations among generations. Delaying parenthood is a recent strategy adopted by women interested in careers especially those with higher education and by couples with an idea of adulthood that does not include parenting. (authors)

Journal ArticleDOI
TL;DR: In this paper, the "wealth flows theory" of fertility transition is applied to historical population change and several problems are identified and explained, and two distinct values of children are discussed: as a source of strength for protection, and as source of wealth gained from a situational advantage in families.
Abstract: The "wealth flows theory" of fertility transition is applied here to historical population change and several problems are identified and explained. 2 distinct values of children are discussed: as a source of strength for protection as a source of wealth gained from a situational advantage in families where there is segmentation by age sex marital status and relationships in work inputs and consumption. It is argued that the balance between the values derived from these 2 sources changes over time. Much of traditional culture is concerned with maintaining the situational balance. The transformation of the cultural superstructure and of the value of children is examined during a transition from a system of familial production to one where much work is allocated by an external labor market. Late marriage of women in Europe before the later decades of the 19th century is discussed and the conclusion is reached that this had little to do with the desire to control the ultimate size of the family. It is argued that slow declines in fertility before the major transition may arise from changes in the locus of fertility decision making and in greater importance being given to the dislike by women of too many pregnancies births and periods with very young children. Why investment in children is possible when no other form of investment can be undertaken is also discussed. The contrast between western family and demographic change with no preexisting models and those found in a situation where a global economy and society are coming into being is examined. It is argued that no explanation of social and economic change is valid which cannot explain the demographic changes of the last 100 years. (Authors)


Journal ArticleDOI
TL;DR: Multivariate analysis of the 1974 Malaysian Fertility and Family Survey suggests that normative conflicts between working and mothering affect the employment-fertility relationship in Malaysia more than spacio-temporal conflicts do.
Abstract: Multivariate analysis of the 1974 Malaysian Fertility and Family Survey tests the hypothesis that an inverse relationship between women’s work and fertility occurs only when there are serious conflicts between working and caring for children. The results are only partly consistent with the hypothesis and suggest that normative conflicts between working and mothering affect the employment-fertility relationship in Malaysia more than spacio-temporal conflicts do. The lack of consistent evidence for the hypothesis, as well as some conceptual problems, lead us to propose an alternative framework for understanding variation in the employment-fertility relationship, both in Malaysia and elsewhere. This framework incorporates ideas from the role incompatibility hypothesis but views the employment-fertility relationship as dependent not just on role conflicts but more generally on the structure of the household’s socioeconomic opportunities.


Journal ArticleDOI
TL;DR: In this article, the extent to which husbands and wives agree in their attitudes toward a number of key issues that may affect fertility behavior was analyzed using cross-sectional surveys in a developing society, Taiwan.
Abstract: Analysis of the extent to which husbands and wives agree in their attitudes toward a number of key issues that may affect fertility behavior shows that although aggregate views of men and women are remarkably similar, marital couples are frequently in disagreement, particularly if measures discounting for chance agreement of responses are employed. In other words, we cannot accept either the husband or the wife as a surrogate respondent. These conclusions are based on data from cross-sectional surveys in a developing society, Taiwan, of 2000 couples in which the wife was of childbearing age. The impact on fertility of such marital disagreement varies with the attitude in question. Followup birth data over a four-year period indicate that, when there is disagreement, it is the wife's attitude that has more influence on fertility, particularly if she has the stronger belief about the future security and status to be derived from a large family and from sons.

Journal ArticleDOI
TL;DR: Using a 3-stage model of fertility as its theoretical framework anthropological and survey data from a semirural Mexican community are presented to illustrate the cultural obstacles that have hindered fertility decision making in the preconception stage and have channeled decision making on fertility regulation into the pregnancy and postnatal stages.
Abstract: Using a 3-stage model of fertility as its theoretical framework anthropological and survey data from a semirural Mexican community are presented to illustrate the cultural obstacles that have hindered fertility decision making in the preconception stage and have channeled decision making on fertility regulation into the pregnancy and postnatal stages. Although women perceived their susceptibility to conception a number of factors reduced their motivation or ability to regulate fertility. Among women or couples for whom the salience of fertility and motivation to limit family size was high contraception abstinence and lactation seemed to be the most widely known accepted and available methods to reduce susceptibility to conception. Other alternatives following birth included lending out the children during temporary periods of economic stress and in extreme cases infanticide. (Authors)

Journal ArticleDOI
TL;DR: Although there is little supporting evidence for any convergence in state fertility rates for the period 1940 to 1977, birth expectations data for women 18 to 29 years old for 1977 and 1978 indicate a fairly uniform expected family size of two children per woman.
Abstract: This study examines whether or not various underlying assumption employed in state fertility projections are justified. It uses birth expectations data from recent June fertility supplements to the Current Population Survey (CPS) which is a national probability sample of about 55000 interviewed households in the US and new estimates of fertility rates for states for intercensal years. The evidence for any convergence or divergence in fertility rates for states was analyzed between 1940-77 and the correspondence between actual and expected fertility among states for the 1977-78 period was examined. The relative variation in the fertility rates in the US decreased by almost 1/2 during the 1940-60 period remained fairly constant through 1970 but doubled by 1977 to a level (0.179) exceeding that shown for 1940 (0.163). This reduction and subsequent increase in the relative variation in the state fertility rates was due to the fact that both the greatest increase in fertility during the 1940-60 period and the greatest decline during the 1960-77 period occurred in the states that had the lowest fertility rates principally the Northeast and North Central states. Even within the 2 major regions the relative variation in fertility rates among the states followed the same pattern as the US as a whole although the level of variation for the South was much less than that of the rest of the country for all of the periods shown. Overall the difference between the South and the non-South in the total fertility rate (TFR) fell from being 19% higher in the South in 1940 to essentially the same rate in 1960 to around 6% higher in the South in the mid 1970s. Although regional fertility differences between the South and the rest of the US appear to be of lessening importance individual differences in state TFRs were still evident. If anything the data showed that the new emerging geographical stratifier may be costal versus interior states. The findings suggest a careful reexamination of state fertility projection assumptions particularly those that involve the linking of state to national fertility projection paths and levels. Although there was little supporting evidence for any convergence in state fertility rates for the 1940-77 period birth expectations data for women 18-29 years old for 1977 and 1978 indicated a fairly uniform expected family size of 2 children/woman.



Journal ArticleDOI
TL;DR: Analysis of children ever born and of parity progression show that current religious choice is more important in explaining fertility than is religion of orientation or denomination of secondary school.
Abstract: Longitudinal data from a large .sample of Wisconsin men and women are used to examine the effects on fertility of religious and secular socialization, including farm upbringing. Analyses of children ever born (CEB) and of parity progression show that current religious choice is more important in explaining fertility than is religion of orientation or denomination of secondary school. The effects of current and background religion are additive, and the effect of current religion is the same for men as for women at each parity progression. Catholic religious background affects fertility primarily by increasing the likelihood of having a third or fourth child; its indirect effects on fertility operate through religious schooling and current religious affiliation. Unlike religious background, the positive influence of farm background on fertility persists among men and women, even when current farm employment is controlled.

Journal ArticleDOI
TL;DR: In this paper, the authors address the claim that Tibet has experienced a population decline since the 7th century due to low fertility levels influenced by cultural and psychological factors and as such represents an anomalous peasant society.
Abstract: Addresses the claim that Tibet has experienced a population decline since the 7th century due to low fertility levels influenced by cultural and psychological factors and as such represents an anomalous peasant society. Data from several recent studies do not support this contention. Fertility levels were found to be high enough to produce substantial population growth. At the assumed fertility levels a very high mortality level (about 74% for female children) would be necessary to achieve homeostasis in population levels. The study also shows sociocultural but not psychological effects on fertility behavior. It is suggested that these factors affected fertility levels even more in the past. Overall the data point to a peasant population characterized by high mortality balancing moderate to low fertility. It appears that biocultural factors reducing fertility must have played a large role in producing the low rates of population growth that characterize Tibet before the mid 18th century demographic transition.