First Birth (first + birth)

Distribution by Scientific Domains


Selected Abstracts


Universal versus Economically Polarized Change in Age at First Birth: A French,British Comparison

POPULATION AND DEVELOPMENT REVIEW, Issue 1 2009
Michael S. Rendall
France and Britain in the 1980s and 1990s represented two contrasting institutional models for the integration of employment and motherhood: the "universalistic" regime in France offered subsidized childcare and maternity-leave benefits at all income levels; the "means-tested" regime in Britain mainly offered income-tested benefits for single mothers. Comparing the two countries, we test the hypothesis that the socioeconomic gradient of fertility timing has become increasingly mediated by family policy. We find increasing polarization in women's age at first birth by pre-childbearing occupation in Britain but not in France. Early first births persisted in Britain only among women in low-skill occupations, while shifts toward increasingly late first births occurred in clerical/secretarial occupations and higher occupational groups. Age at first birth increased across all occupations in France, but age at first birth in France was still much earlier on average than for all but low-skill British mothers. [source]


WHY WAIT?: EXAMINING DELAYED WIC PARTICIPATION AMONG PREGNANT WOMEN

CONTEMPORARY ECONOMIC POLICY, Issue 4 2008
LAURA TIEHEN
Despite the benefits of prenatal participation in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), many eligible women either do not participate or begin participation late in their pregnancies. Using recent nationally representative data, we find that more disadvantaged women are more likely to access WIC and, with some notable exceptions, to participate earlier in their pregnancies. Hispanic women, especially those with language difficulties, enroll in WIC later in their pregnancies. Early WIC participation, particularly among teenagers, is less likely among women experiencing a first birth and depends on the mother's early recognition of her pregnancy. (JEL I18, I30) [source]


A case-control study on hormone therapy as a risk factor for breast cancer in Finland: Intrauterine system carries a risk as well

INTERNATIONAL JOURNAL OF CANCER, Issue 2 2010
Heli K. Lyytinen
Abstract The purpose of this study was to evaluate the association between postmenopausal hormone therapy (HT) and the risk for breast cancer in recently postmenopausal Finnish women. All Finnish women with first invasive breast cancer diagnosed between the ages of 50 and 62 years during 1995,2007 (n = 9,956) were identified from the Finnish Cancer Registry. For each case, 3 controls of the same age were retrieved from the Finnish Population Register. The cases and controls were linked to the national medical reimbursement register to assess the use of HT. The odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer were calculated with conditional logistic regression analysis, adjusting for parity, age at the first birth and health care district. Estradiol-only therapy (991 users with breast cancer, n) or oral progestagen (n = 138) was not accompanied by an increased risk. Estradiol-progestagen therapy (EPT) (n = 1,731) was associated with an elevated risk in the whole series (OR 1.36; 95% CI 1.27,1.46). The risk became detectable in less than 3 years of use. Continuous EPT use tended to be associated with a higher risk for breast cancer than the sequential EPT use. The use of tibolone (n = 80) (1.36; 1.15,1.96), a levonorgestrel-releasing intrauterine system (LNG,IUS) alone (n = 154) (1.45; 1.97,1.77) or as a complement to estradiol (n = 137) (2.15; 1.72,2.68) was also associated with an increased risk. The association between HT use and the risk for breast cancer shows a large variation between various forms of HT, and also the use of LNG-IUS may carry a risk. [source]


Reproductive factors, exogenous hormone use and bladder cancer risk in a prospective study,

INTERNATIONAL JOURNAL OF CANCER, Issue 10 2006
Marie M. Cantwell
Abstract Sex is a consistent predictor of bladder cancer: men experience 2,4-fold higher age-adjusted rates than women in the U.S. and Europe. The objective of this study was to examine whether hormone-related factors are associated with bladder cancer in women. We examined parity, age at menarche, age at first birth, age at menopause, oral contraceptive use and menopausal hormone therapy (HT) use and bladder cancer risk in the Breast Cancer Detection Demonstration Project Follow-Up Study. Endpoint and exposure information was collected on 54,308 women, using annual telephone interviews (1980,86) and 3 mailed, self-administered questionnaires (1987,98). During an average follow-up time of 15.3 years, 167 cases of bladder cancer were identified. Univariate and adjusted rate ratios (RRs) were estimated using Poisson regression. Parity, age at menarche, age at first birth, age at menopause, and oral contraceptive use were not associated with bladder cancer risk. The majority of menopausal women who took HT used estrogen therapy (ET). Postmenopausal women with less than 4 years, 4,9 years, 10,19 years and 20 or more years of ET use had RRs of 1.55 (95% CI = 0.96,2.51), 1.00 (95% CI = 0.49,2.04), 1.23 (95% CI = 0.62,2.43) and 0.57 (95% CI = 0.14,2.34), respectively, compared with nonusers (p = 0.50). Findings from this study are not consistent with the hypothesis that hormone-related factors in women are associated with bladder cancer. © 2006 Wiley-Liss, Inc. [source]


Education and risk of breast cancer in the Norwegian-Swedish women's lifestyle and health cohort study

INTERNATIONAL JOURNAL OF CANCER, Issue 4 2004
Tonje Braaten
Abstract A positive relationship between level of education and female breast cancer risk is well supported by scientific evidence, but few previous studies could adjust for all relevant potential confounding factors. The authors' purpose was to examine how risk for breast cancer varies with level of education and to identify factors that explain this variation, using data from a prospective cohort study including 102,860 women from Norway and Sweden who responded to an extensive questionnaire in 1991/1992; 1,090 incident primary invasive breast cancer cases were revealed during follow-up, which ended in December 1999. The Cox Proportional Hazards Model was used to calculate relative risks (RR) with 95% confidence intervals (CI). Women with more than 16 years of education had a 36% increased risk compared to the lowest educated (7,9 years) (Age adjusted RR=1.36, 95% CI: 1.10, 1.68). This relationship was slightly stronger among postmenopausal (RR 1.51) than among premenopausal (RR 1.25) women. In both groups, however, the relative risk estimates turned close to unity by adjustment for parity, age at first birth, body mass index (BMI), height, age at menarche, menopausal status, use of oral contraceptives and consumption of alcohol. The overall multivariate relative risk among the highest educated women was 1.04 (95% CI 0.82,1.32). The results of our study suggest a clear positive gradient in risk for breast cancer by level of education, which can be fully explained by established breast cancer risk factors. © 2004 Wiley-Liss, Inc. [source]


Early age reproduction in female savanna elephants (Loxodonta africana) after severe poaching

AFRICAN JOURNAL OF ECOLOGY, Issue 2 2009
M. J. Owens
Abstract A 10-year study revealed that after severe poaching (>93% killed) of elephants (Loxodonta africana) in Zambia's North Luangwa National Park (NLNP) during the 1970s and 1980s, the age of reproduction in females was greatly reduced. Fifty-eight per cent of births were delivered by females aged 8.5,14 years, an age at which elephants were reported to be sexually immature in nearby South Luangwa National Park (SLNP) before poaching. The mean age of females at first birth (AFB) (1993, 1994) was 11.3 years. Prior to poaching, the mean age AFB in SLNP was 16 years. The NLNP age structure and sex ratio were skewed, mean family unit size was reduced, and 37% of family units contained no females older than 15 years. Twenty-eight per cent of family units were comprised entirely of a single mother and her calf, and 8% of units consisted only of orphans who would have been considered sexually immature prior to poaching. Only 6% of survivors were older than 20 years, the age at which females in little-poached populations generally become most reproductively active. After a community-based conservation programme and the UN-CITES ban on the ivory trade were introduced, no elephants were recorded killed. In spite of a high reproductive rate, 6 years after poaching decreased, the density of the NLNP population had not increased, supporting predictions that the removal of older matriarchs from family units will have serious consequences on the recovery of this species. Résumé Une étude qui a duré dix ans a révélé qu'après un braconnage très grave (>93% tués) des éléphants (Loxodonta africana) dans le Parc National de Luangwa Nord (NLNP), en Zambie au cours des années 1970 et 1980, l'âge de la reproduction chez les femelles a fort baissé. Cinquante-huit pour cent des naissances se sont passées chez des femelles qui avaient entre 8,5 et 14 ans, un âge auquel les éléphants étaient dits être encore sexuellement immatures dans le Parc National de Luangwa Sud (SLNP), tout proche, avant le braconnage. L'âge moyen des femelles à la première mise-bas (AFB ,at first birth) (1993, 1994) était de 11,3 ans. Avant le braconnage, l'âge moyen à la première mise-bas était de 16 ans au SLNP. Au NLNP, la structure d'âge et le sex-ratio ont été faussés, la taille moyenne de l'unité familiale a été réduite, et 37% des familles ne contiennent aucune femelle de plus de 15 ans. Vingt-huit pour cent des unités familiales n'étaient composées que d'une mère seule et de son jeune, et huit pour cent n'étaient composées que d'orphelins qui devaient être considérés comme sexuellement immatures avant le braconnage. Seuls six pour cent des survivants avaient plus de 20 ans, l'âge auquel les femelles de populations peu braconnées deviennent généralement les plus actives en matière de reproduction. Après l'introduction d'un programme de conservation communautaire et l'interdiction, par la CITES-UN, du commerce de l'ivoire, on n'a plus enregistré aucun massacre d'éléphant. Malgré un taux élevé de reproduction, la densité de population du NLNP n'a pas augmenté, ce qui conforte les prédictions que l'enlèvement des plus vieilles matriarches des unités familiales aura de sérieuses conséquences sur la restauration de cette espèce. [source]


Childhood, adolescence, and longevity: A multilevel model of the evolution of reserve capacity in human life history

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2009
Barry Bogin
The grandmother hypothesis (GH) of Hawkes et al. ([1998]: Proc Natl Acad Sci USA 95: 1336,1339) finds that selection for lower adult mortality and greater longevity allow for the evolution of prolonged growth in human beings. In contrast, other researchers propose that the evolution of the human childhood and adolescent stages of life history prolonged the growth period and allowed for greater biological resilience and longevity compared with apes. In this article, the GH model is reanalyzed using new values for some of its key variables. The original GH set the age at human feeding independence at 2.8 years of age (weaning) and used demographic data from living foragers to estimate average adult lifespan after first birth at 32.9 years. The reanalysis of the GH uses age 7.0 years (end of the childhood stage) as the minimum for human feeding independence and uses data from healthier populations, rather than foragers, to derive an estimate of 48.9 years for average adult life span. Doing so finds that selection operated to first shorten the infancy stage (wean early compared with apes), then prolong the growth period, and finally result in greater longevity. The reanalysis provides a test of the reserve capacity hypothesis as part of a multilevel model of human life history evolution. Am. J. Hum. Biol. 2009. © 2009 Wiley-Liss, Inc. [source]


Taller women do better in a stressed environment: Height and reproductive success in rural Guatemalan women

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2008
Thomas V. Pollet
Previous research on the relationship between height and reproductive success in women has produced mixed results. One possible explanation for these is mediation by ecological factors, such as environmental stress. Here we investigate female height and reproductive success under conditions of environmental stress (poverty) using a large scale dataset from Guatemala (n = 2,571). Controlling for educational attainment, age and ethnicity, we examined relationships between height and childlessness, occurrence of a stillbirth, fertility and child survival. There was no significant relationship between height and never haven given birth. Extremely short women had a significantly raised likelihood of experiencing stillbirth. There were curvilinear relationships between height and age at first birth, fertility, and survival rates for children. Overall, though, the penalties for short stature, particularly in terms of child survival, were far greater than those associated with extreme tallness, and so female height is positively associated with overall fitness in this population. Am. J. Hum. Biol., 2008. © 2008 Wiley-Liss, Inc. [source]


An evolutionary ecological perspective on demographic transitions: Modeling multiple currencies

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 2 2002
Bobbi S. Low
Life history theory postulates tradeoffs of current versus future reproduction; today women face evolutionarily novel versions of these tradeoffs. Optimal age at first birth is the result of tradeoffs in fertility and mortality; ceteris paribus, early reproduction is advantageous. Yet modern women in developed nations experience relatively late first births; they appear to be trading off socioeconomic status and the paths to raised SES, education and work, against early fertility. Here, [1] using delineating parameter values drawn from data in the literature, we model these tradeoffs to determine how much socioeconomic advantage will compensate for delayed first births and lower lifetime fertility; and [2] we examine the effects of work and education on women's lifetime and age-specific fertility using data from seven cohorts in the Panel Study of Income Dynamics (PSID). Am. J. Hum. Biol. 14:149,167, 2002. © 2002 Wiley-Liss, Inc. [source]


Universal versus Economically Polarized Change in Age at First Birth: A French,British Comparison

POPULATION AND DEVELOPMENT REVIEW, Issue 1 2009
Michael S. Rendall
France and Britain in the 1980s and 1990s represented two contrasting institutional models for the integration of employment and motherhood: the "universalistic" regime in France offered subsidized childcare and maternity-leave benefits at all income levels; the "means-tested" regime in Britain mainly offered income-tested benefits for single mothers. Comparing the two countries, we test the hypothesis that the socioeconomic gradient of fertility timing has become increasingly mediated by family policy. We find increasing polarization in women's age at first birth by pre-childbearing occupation in Britain but not in France. Early first births persisted in Britain only among women in low-skill occupations, while shifts toward increasingly late first births occurred in clerical/secretarial occupations and higher occupational groups. Age at first birth increased across all occupations in France, but age at first birth in France was still much earlier on average than for all but low-skill British mothers. [source]


Childbearing and Women's Survival: New Evidence from Rural Bangladesh

POPULATION AND DEVELOPMENT REVIEW, Issue 3 2003
Jane Menken
Effects of childbearing on women's mortality and the implications of family planning programs in reducing these effects are examined in a 20-year prospective study of more than 2,000 women in Matlab, Bangladesh. Maternal mortality is defined as a death occurring in the six weeks after childbirth. But childbearing may affect women's survival beyond this brief period. Additional hypotheses considered relate to 1) cumulative exposure to childbearing, whether measured by parity or pace of childbearing, 2) age at first birth, and 3) effects beyond the reproductive ages. The results offer no support to cumulative exposure hypotheses, showing no link between parity or pace of childbearing and mortality risk. Instead, we identify an extended period of heightened mortality risk associated with each birth,the year of the birth and the two subsequent years. Family planning programs, by reducing the number of children and therefore a woman's exposure to extended maternal mortality risk, potentially increase survival. Research is needed to identify and address the specific causes of extended maternal mortality risk so that appropriate ameliorative programs may be developed. [source]


Synchrony between growth and reproductive patterns in human females: Early investment in growth among Pumé foragers

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010
Karen L. Kramer
Abstract Life history is an important framework for understanding many aspects of ontogeny and reproduction relative to fitness outcomes. Because growth is a key influence on the timing of reproductive maturity and age at first birth is a critical demographic variable predicting lifetime fertility, it raises questions about the synchrony of growth and reproductive strategies. Among the Pumé, a group of South American foragers, young women give birth to their first child on average at age 15.5. Previous research showed that this early age at first birth maximizes surviving fertility under conditions of high infant mortality. In this study we evaluate Pumé growth data to test the expectation that if early reproduction is advantageous, then girls should have a developmental trajectory that best prepares them for young childbearing. Analyses show that comparatively Pumé girls invest in skeletal growth early, enter puberty having achieved a greater proportion of adult body size and grow at low velocities during adolescence. For early reproducers growing up in a food-limited environment, a precocious investment in growth is advantageous because juveniles have no chance of pregnancy and it occurs before the onset of the competing metabolic demands of final reproductive maturation and childbearing. Documenting growth patterns under preindustrial energetic and demographic conditions expands the range of developmental variation not otherwise captured by normative growth standards and contributes to research on human phenotypic plasticity in diverse environments. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source]


Beginning IVF Treatments After Age 30 Increases the Risk of Breast Cancer: Results of a Case,Control Study

THE BREAST JOURNAL, Issue 6 2008
Daniela Katz MD
Abstract:, The long-term risks of in vitro fertilization (IVF) treatment remain unclear. This study was designed to determine breast cancer risk factors in women who underwent IVF, and to establish characteristics of these tumors. Records of 7,162 consecutive women who underwent IVF at a single center between 1984 and 2002 were linked with the Israel Cancer Registry to identify women who developed breast cancer. IVF-related parameters were compared between 28 breast cancer patients who had undergone IVF (IVF BC) and for whom complete IVF data were available with 140 women who underwent IVF and did not develop breast cancer (IVF non-BC). Tumor parameters were compared between 38 patients who developed breast cancer after IVF and 114 age-matched breast cancer patients who did not undergo IVF (non-IVF BC). Age over 30 at the time of first IVF treatment, even after controlling for age at first birth, was the only parameter significantly associated with increased breast cancer risk (RR = 1.24, p = 0.02, 95% CI = 1.03,1.48). There were no differences between IVF-BC and IVF non-BC patients in all other IVF-related parameters. The only statistically significant difference in tumors developing in IVF-BC patients compared with non-IVF BC patients was in grade distribution, particularly for grade II tumors. However, the significance of such a difference is unclear. Women who start IVF after the age of 30 appear to be at increased risk of developing breast cancer. The characteristics of breast tumors in women who underwent IVF are no different than in patients without previous exposure to IVF. [source]


From Adjuvant Therapy to Breast Cancer Prevention: BCPT and STAR

THE BREAST JOURNAL, Issue 3 2001
Barbara K. Dunn MD
Abstract: The continued widespread prevalence of breast cancer supports placing a high priority on research aimed at its primary prevention, particularly among women who are at increased risk for developing this disease. The suggestion of potential agents for the primary chemoprevention of breast cancer evolved out of the treatment setting. Extensive experience with tamoxifen, a first-generation selective estrogen receptor modulator (SERM) showing efficacy, first, in the treatment of advanced breast cancer and, subsequently, as adjuvant therapy for early stage disease established the safety of this agent. Cumulative data from multiple adjuvant studies documented the efficacy of tamoxifen in reducing second primary breast cancers in the contralateral breast, supporting its potential as a chemopreventive agent for breast cancer. The safety and second primary data on tamoxifen, together with extensive information on its pharmacokinetics, metabolism, and antitumor effects, as well as its potentially beneficial effects on lipid metabolism and osteoporosis, led the National Surgical Adjuvant Breast and Bowel Project (NSABP) to select tamoxifen for testing in the first prospective randomized phase III trial of the efficacy of a chemopreventive agent for preventing breast cancer in women at increased risk of the disease. Accordingly, in 1992 the NSABP started the Breast Cancer Prevention Trial (P-1) in which 13,388 women 35 years of age who were at increased risk of breast cancer according to Gail model risk factors [family history, age, and personal history (i.e., age at first birth, age at menarche, previous breast biopsies)] were randomized to tamoxifen 20 mg/day or placebo for 5 years. Through 69 months of follow-up tamoxifen reduced the risk of invasive breast cancer, primarily estrogen receptor-positive tumors, by 49% (two-sided p < 0.00001). Tamoxifen reduced the risk of noninvasive breast cancer by 50% (two-sided p < 0.002). In addition, tamoxifen reduced fractures of the hip, radius, and spine, but it had no effect on the rate of ischemic heart disease. As previously shown, the rates of endometrial cancer and vascular events increased with tamoxifen. With the P-1 results establishing tamoxifen as the standard of care for the primary chemoprevention of breast cancer in high-risk women, concern over the side effects of tamoxifen has prompted a continuing search for an agent that displays a more desirable efficacy/toxicity profile. Raloxifene, a second-generation SERM approved for the prevention of osteoporosis in postmenopausal women, displays antiestrogenic properties in the breast and possibly the endometrium, and estrogenic effects in the bone and on the lipid profile, suggesting it as a candidate for comparison with the chemopreventive standard, tamoxifen. Raloxifene will be compared to tamoxifen in an equivalency trial, the Study of Tamoxifen and Raloxifene (STAR) NSABP P-2, which began in July 1999 at almost 500 centers in North America. The plan is to randomize 22,000 postmenopausal women 35 years of age at increased risk of breast cancer by Gail criteria to tamoxifen 20 mg/day or raloxifene 60 mg/day for 5 years. Study endpoints include invasive and noninvasive breast cancer, cardiovascular disease, endometrial cancer, bone fractures, and vascular events. [source]


Children and Women's Hours of Work,

THE ECONOMIC JOURNAL, Issue 526 2008
Gillian Paull
The prevalence of women in part-time work continues to be a distinguishing feature of female employment in Britain. Using data from the BHPS, this article analyses the evolution of work hours for women and men during family formation and development. A substantial movement towards part-time work for women occurs with the first birth and continues steadily for ten years. The gender gap in hours subsequently diminishes but persists even after children have grown up. Births have little impact on men's hours, although there is some adjustment in the balance of work hours for couples following births and last school entry. [source]


Reproductive parameters of wild Trachypithecus leucocephalus: seasonality, infant mortality and interbirth interval

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 7 2009
Tong Jin
Abstract Understanding the reproductive parameters of endangered primate species is vital for evaluating the status of populations and developing adequate conservation measures. This study provides the first detailed analysis of the reproductive parameters of wild white-headed langurs (Trachypithecus leucocephalus), based on demographic data collected over an 8-year period in the Nongguan Karst Hills in Chongzuo County, Guangxi, China. From 1998 to 2002, a total of 133 live births were recorded in the population based on systematic censuses. Births occurred throughout the year, but the temporal pattern was highly correlated with seasonal variation in temperature and rainfall, with the birth peak coinciding with the dry and cold months of November,March. The average birthrate was 0.47±0.13 births per female per year and mortality for infants younger than 20 months was 15.8%. From 1998 to 2006, 14 females gave birth to 41 infants in four focal groups. The average age at first birth for female langurs was 5,6 years (n=5) and the interbirth interval (IBI) was 23.2±5.2 months (median=24.5 months, n=27). Infants are weaned at 19,21 months of age. The IBI for females with infant loss before weaning was significantly shorter than those for females whose infants survived. It appears that birth seasonality in the white-headed langurs is influenced by seasonal changes in food availability. The timing of conceptions was found to coincide with peak food availability. The reproductive parameters for white-headed langurs reported here are quite similar to those reported for other colobine species. One major difference is our observation of lower infant mortality in Trachypithecus. Am. J. Primatol. 71:558,566, 2009. © 2009 Wiley-Liss, Inc. [source]


Reproductive aging in captive and wild common chimpanzees: factors influencing the rate of follicular depletion

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2009
Sylvia Atsalis
Abstract We examine and discuss evidence of contrasting differences in fertility patterns between captive and wild female chimpanzees, Pan troglodytes, as they age; in the wild females reproduce in their 40s, but captive studies suggest that menopause occurs around that time. Thus, despite the increased longevity generally observed in captive populations reproductive life span is shortened. We outline a hypothesis to explain the apparent differential pace of reproductive decline observed between wild and captive populations. The breeding schedules of captive primates may contribute to accelerated reproductive senescence because continuous cycling in captive animals results in early depletion of the ovarian stock and premature senescence. Available evidence supports the hypothesis that women with patterns of high oocyte loss experience earlier menopause. Chimpanzees in captivity live longer, and thus, similar to humans, they may experience follicular depletion that precedes death by many years. In captivity, chimpanzees typically have an early age at menarche and first birth, shorter interbirth intervals associated with short lactational periods as young mature faster, and nursery rearing, which allows mothers to begin cycling earlier. Variables typical of wild chimpanzee populations, including late age at menarche and first birth, long interbirth intervals associated with prolonged lactational periods, and a long period of female infertility after immigration, spare ovulations and may be responsible for the later age at reproductive termination. Finally, we describe and discuss the timing of specific reproductive landmarks that occur as female chimpanzees age, distinguishing between functional menopause (age at last birth) and operational menopause (end of cycling). Am. J. Primatol. 71:271,282, 2009. © 2008 Wiley-Liss, Inc. [source]


Ultrasonography and Sex Ratios in China

ASIAN ECONOMIC POLICY REVIEW, Issue 1 2009
Hongbin LI
J13; J16; O10 This paper directly measures the causal effects of sex-selective abortions on the sex ratio at birth by exploiting the exogenous county-level variation in the availability of B-ultrasound machines. Using data from the 1990 Census of Fujian Province and local records on the introduction time of B-ultrasound machines, we find that the availability of B-ultrasound machines increases the sex ratio at birth by 0.025 in rural areas and 0.117 in urban areas. The rise of sex ratio is especially significant for second births in rural areas when the first birth is a girl. [source]


Infertility in Australia circa 1980: an historical population perspective on the uptake of fertility treatment by Australian women born in 1946-51

AUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 6 2009
Danielle L. Herbert
Abstract Objective: To estimate the prevalence of lifetime infertility in Australian women born in 1946-51 and examine their uptake of treatment. Methods: Participants in the Australian Longitudinal Study on Women's Health born in 1946-51 (n=13,715) completed up to four mailed surveys from 1996 to 2004. The odds of infertility were estimated using logistic regression with adjustment for socio-demographic and reproductive factors. Results: Among participants, 92.1% had been pregnant. For women who had been pregnant (n=12738): 56.5% had at least one birth but no pregnancy loss (miscarriage and/or termination); 39.9% experienced both birth and loss; and 3.6% had a loss only. The lifetime prevalence of infertility was 11.0%. Among women who reported infertility (n=1511), 41.7% used treatment. Women had higher odds of infertility when they had reproductive histories of losses only (OR range 9.0-43.5) or had never been pregnant (OR=15.7, 95%CI 11.8-20.8); and higher odds for treatment: losses only (OR range 2.5-9.8); or never pregnant (1.96, 1.28-3.00). Women who delayed their first birth until aged 30+ years had higher odds of treatment (OR range 3.2-4.3). Conclusions: About one in ten women experienced infertility and almost half used some form of treatment, especially those attempting pregnancy after 1980. Older first time mothers had an increased uptake of treatment as assisted reproductive technologies (ART) developed. Implications: This study provided evidence of the early uptake of treatment prior to 1979 when the national register of invasive ART was developed and later uptake prior to 1998 when data on non-invasive ART were first collected. [source]


Risk factors for uterine rupture and neonatal consequences of uterine rupture: a population-based study of successive pregnancies in Sweden

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 10 2007
M Kaczmarczyk
Objective, Uterine rupture is a rare but a catastrophic event. The aim of the present study was to explore the risk factors for uterine rupture and associated neonatal morbidity and mortality among a cohort of Swedish women attempting vaginal birth in their second delivery. Design, Population-based cohort study. Setting, Sweden. Population, A total of 300 200 Swedish women delivering two single consecutive births between 1983 and 2001. Methods, Swedish population-based registers were used to obtain information concerning demographics, pregnancy and birth characteristics, and neonatal outcomes. Logistic regression was used to analyse potential risk factors for uterine rupture and risk of neonatal mortality associated with uterine rupture. Odds ratios were used to estimate relative risks using 95% CI. Main outcome measure, Uterine rupture and neonatal mortality in the second pregnancy. Results, Compared with women who delivered vaginally in their first birth, women who underwent a caesarean delivery were, during their second delivery, at increased risk of uterine rupture (adjusted OR 41.79; 95% CI 29.73,57.00). Induction of labour, high (,4000 g) birthweight, postterm (,42 weeks) births, high (,35 years) maternal age, and short (,164 cm) maternal stature were also associated with increased risk of uterine rupture. Uterine rupture was associated with a substantially increased risk in neonatal mortality (adjusted OR 65.62; 95% CI 32.60,132.08). Conclusion, The risk of uterine rupture in subsequent deliveries is not only markedly increased among women with a previous caesarean delivery but also influenced by induction of labour, birthweight, gestational age, and maternal characteristics. [source]


Premature death among teenage mothers

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 8 2004
Petra Otterblad Olausson
Objective Some data suggest an association between teenage childbearing and premature death. Whether this possible increase in risk is associated with social circumstances before or after childbirth is not known. We studied premature death in relation to age at first birth, social background and social situation after first birth. Design Population-based cohort study. Setting Women born in Sweden registered in the 1985 Swedish Population Census. Population Swedish women born 1950,1964 who had their first infant before the age of 30 years (N= 460,434). Methods Information on the women's social background and social situation after first birth was obtained from Population Censuses. The women were followed up with regard to cause of death from December 1, 1990 to December 31, 1995. Mortality rate ratios and 95% confidence intervals (CI) were calculated. Main outcome measures Mortality rates by cause of death. Results Independent of socio-economic background, teenage mothers faced an increased risk of premature death later in life compared with older mothers (rate ratio 1.6, 95% CI 1.4,1.9). The increased risk was most evident for deaths from cervical cancer, lung cancer, ischaemic heart disease, suicide, inflicted violence and alcohol-related diseases. Some, but not all, of these increases in risk were associated with the poorer social position of teenagers mothers. Conclusions Teenage mothers, independent of socio-economic background, face an increased risk of premature death. Strategies to reduce teenage childbearing are likely to contribute to improved maternal and infant health. [source]


A prospective study of reproductive and menstrual factors and colon cancer risk in Japanese women: Findings from the JACC study

CANCER SCIENCE, Issue 7 2004
Koji Tamakoshi
The effects of reproductive factors on the etiology of colon cancer in Asian populations remain unexplored. So we examined 38,420 Japanese women aged 40-79 years who responded to a questionnaire on reproductive and other lifestyle factors from 1988 to 1990 in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. During an average 7.6 years of follow-up, we documented 207 incident colon cancers. Multivariate analysis indicated that colon cancer risk was likely to be lower among pa-rous women than among nulliparous. Women who had two abortions or more had a 72% higher risk of developing colon cancer [relative risk (RR) 1.72; 95% confidence interval (CI) 1.16-2.55; trend P<0.01] compared with women who never had an abortion. The RR of colon cancer among postmenopausal women significantly decreased with increasing age at menarche (trend P=0.01). No apparent association between colon cancer and gravida, age at first birth, age at menopause, or duration of menstruation was seen. These prospective data support the hypothesis that female reproductive events modify colon cancer risk, and suggest that reproductive factors, particularly age at menarche and having an abortion, may be of importance in the etiology of colon cancer among Japanese women. [source]


Which mothers wean their babies prematurely from full breastfeeding?

ACTA PAEDIATRICA, Issue 8 2009
An Australian cohort study
Abstract Aim:, To identify the maternal and infant characteristics associated with an early transition from full breastfeeding to complementary or no breastfeeding during the first 2 months of life in a large, representative cohort of Australian infants. Method:, Multinomial logistic modelling was performed on data for infants with complete breastfeeding and sociodemographic data (N = 4679) including maternal age, education, smoking, employment, pregnancy and birth outcomes. Results:, Ninety-one percent of women initiated breastfeeding. Sixty-nine percent of infants were being fully breastfed at 1 month, and 59% were fully breastfed at 2 months. Maternal characteristics , age less than 25 years, smoking in pregnancy, early full-time postnatal employment and less educational attainment , were associated with early breastfeeding cessation. Infant factors , multiple birth, caesarean birth, infant or first birth , were associated with a transition to complementary breastfeeding in the first postnatal month. Conclusion:, Breastfeeding duration is substantially affected by breastfeeding outcomes in the first postpartum month. The first month is an important window for evidence-based interventions to improve rates of full breastfeeding in groups of women identified as at risk of early breastfeeding cessation. [source]


Early motherhood and disruptive behaviour in the school-age child

ACTA PAEDIATRICA, Issue 1 2004
P Trautmann-Villalba
Aim: To determine the significance of young maternal age, family adversity and maternal behaviour during mother-toddler interaction in the prediction of child disruptive behaviour at age eight. Methods: From an ongoing longitudinal study of infants at risk for later psychopathology (n= 362), 72 young mothers aged between 15 and 24 y (median 22 y) at first birth were compared with 197 primiparous older mothers ranging in age from 25 to 41 y (median 29 y). Family adversity at childbirth was assessed using a modified version of Rutter's Family Adversity Index (FAI) and measures of child disruptive behaviour at age eight were obtained using Achenbach's Teacher Report Form (TRF). An observational procedure was used to assess maternal behaviour during mother-child interaction at the age of 2 y. Results: Young mothers encountered more adverse family characteristics and were more inadequate, restrictive and more negative during interaction with their toddlers. Their school-aged children showed higher scores on all disruptive behaviour scales of the TRF. Hierarchical regression analyses revealed that family adversity and maternal behaviour during toddler interaction could account for most of the association between early motherhood and child disruptive behaviour. Conclusion: The impact of young motherhood on child mental health is not confined to teenage mothers and is mainly attributed to psychosocial and interactional factors. [source]


Risk factors for pre-eclampsia in nulliparous and parous women: the Jerusalem Perinatal Study

PAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2005
E. F. Funai
Summary Pre-eclampsia has been described as a ,disease of first pregnancies' and many believe that its occurrence in a later pregnancy signals a fundamentally different entity. We sought to compare risk factors in first and subsequent pregnancies. We studied 1319 cases of pre-eclampsia recorded in a historical cohort of 82 436 deliveries in Jerusalem in 1964,76. Logistic regression was used to control for covariates. The adjusted odds ratio (OR) for pre-eclampsia in first births was 2.58 (95% confidence interval[CI] 2.23, 2.97), compared with all later birth order groups, between which there were no detectable differences in risk. Other risk factors included increasing maternal age, diabetes (OR 5.64, 95% CI 4.33, 7.35), multiple gestations (OR 3.38, 95% CI 2.54, 4.49), fetal haemolytic disease (OR 2.24, 95% CI 1.43, 3.50) and lower maternal education. The risk of pre-eclampsia was not associated with the mother's employment outside the home and did not differ between immigrants vs. Israeli-born mothers or between groups of women whose fathers had been born in Western Asia, North Africa or Europe. Effects of each risk factor were similar within first and subsequent births. These results lend no support to the hypothesis that there is a fundamental difference between pre-eclampsia in a first pregnancy compared with that occurring in a later pregnancy; conclusions may be moderated, however, by the knowledge that the incidence of pre-eclampsia was low in this historical cohort. [source]


An evolutionary ecological perspective on demographic transitions: Modeling multiple currencies

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 2 2002
Bobbi S. Low
Life history theory postulates tradeoffs of current versus future reproduction; today women face evolutionarily novel versions of these tradeoffs. Optimal age at first birth is the result of tradeoffs in fertility and mortality; ceteris paribus, early reproduction is advantageous. Yet modern women in developed nations experience relatively late first births; they appear to be trading off socioeconomic status and the paths to raised SES, education and work, against early fertility. Here, [1] using delineating parameter values drawn from data in the literature, we model these tradeoffs to determine how much socioeconomic advantage will compensate for delayed first births and lower lifetime fertility; and [2] we examine the effects of work and education on women's lifetime and age-specific fertility using data from seven cohorts in the Panel Study of Income Dynamics (PSID). Am. J. Hum. Biol. 14:149,167, 2002. © 2002 Wiley-Liss, Inc. [source]


Universal versus Economically Polarized Change in Age at First Birth: A French,British Comparison

POPULATION AND DEVELOPMENT REVIEW, Issue 1 2009
Michael S. Rendall
France and Britain in the 1980s and 1990s represented two contrasting institutional models for the integration of employment and motherhood: the "universalistic" regime in France offered subsidized childcare and maternity-leave benefits at all income levels; the "means-tested" regime in Britain mainly offered income-tested benefits for single mothers. Comparing the two countries, we test the hypothesis that the socioeconomic gradient of fertility timing has become increasingly mediated by family policy. We find increasing polarization in women's age at first birth by pre-childbearing occupation in Britain but not in France. Early first births persisted in Britain only among women in low-skill occupations, while shifts toward increasingly late first births occurred in clerical/secretarial occupations and higher occupational groups. Age at first birth increased across all occupations in France, but age at first birth in France was still much earlier on average than for all but low-skill British mothers. [source]