Reproductive Inequalities Research Articles

Reproductive Inequalities

In the last decade of the twentieth century, the international community shifted its focus to the issue of reproductive rights from a previous emphasis on population control and demographic targets...

Global reproductive inequalities, neo-eugenics and commercial surrogacy in India

India’s commercial surrogacy market literally produces humans and human relationships while sustaining global racial reproductive hierarchies. The post-colonial state’s aggressive anti-natalism echoes the broader global population control agenda framing the global South’s high fertility rates as a ‘global danger’ to be controlled at whatever cost, but is at odds with the neoliberal imperative of unrestrained global fertility tourism. Womb mothers (surrogates) subvert hegemonic discourses by taking control over their bodies and using their fertile bodies ‘productively’. But in controlling their own reproduction through decisions about fertility, sterilization and abortion in order to (re)produce children of higher classes and privileged nations, they ultimately conform to global neo-eugenic imperatives to reduce the fertility of lower class women in the global South. Surrogates creatively construct cross-class, -caste, -religion, -race and -nation kinship ties with the baby and the intended mother, disrupting hegemonic genetic and patriarchal bases of kinship, but fundamentally reify structural inequality.

Queen-worker ratio affects reproductive skew in a socially polymorphic ant.

The partitioning of reproduction among individuals in communally breeding animals varies greatly among species, from the monopolization of reproduction (high reproductive skew) to similar contribution to the offspring in others (low skew). Reproductive skew models explain how relatedness or ecological constraints affect the magnitude of reproductive skew. They typically assume that individuals are capable of flexibly reacting to social and environmental changes. Most models predict a decrease of skew when benefits of staying in the group are reduced. In the ant Leptothorax acervorum, queens in colonies from marginal habitats form dominance hierarchies and only the top‐ranking queen lays eggs (“functional monogyny”). In contrast, queens in colonies from extended coniferous forests throughout the Palaearctic rarely interact aggressively and all lay eggs (“polygyny”). An experimental increase of queen:worker ratios in colonies from low‐skew populations elicits queen–queen aggression similar to that in functionally monogynous populations. Here, we show that this manipulation also results in increased reproductive inequalities among queens. Queens from natural overwintering colonies differed in the number of developing oocytes in their ovaries. These differences were greatly augmented in queens from colonies with increased queen:worker ratios relative to colonies with a low queen:worker ratio. As assumed by models of reproductive skew, L. acervorum colonies thus appear to be capable of flexibly adjusting reproductive skew to social conditions, yet in the opposite way than predicted by most models.

Comparative recruitment, morphology and reproduction of a generalist trematode, Dicrocoelium dendriticum, in three species of host.

Epidemiological rate parameters of host generalist parasites are difficult to estimate, especially in cases where variation in parasite performance can be attributed to host species. Such cases are likely common for generalist parasites of sympatric grazing mammals. In this study, we combined data from experimental exposures in cattle and sheep and natural infections in elk to compare the recruitment, morphology and reproduction of adult Dicrocoelium dendriticum, a generalist trematode that has emerged in sympatric grazing hosts in Cypress Hills Provincial Park, Alberta. Overall, there were no significant differences in the recruitment of metacercariae and in the pre-patency period of adults in experimentally exposed cattle and sheep. All flukes reached reproductive maturity and the degree of reproductive inequality between individual flukes within each infrapopulation was moderate and approximately equal among the three host species. Neither fluke size nor per capita fecundity was constrained by density dependence. Thus, fitness parameters associated with growth and reproduction were approximately equivalent among at least three species of definitive host, two of which are sympatric on pastures in this Park. The generalist life-history strategy of this trematode, which is known to extend to other stages of its life cycle, has likely contributed to its invasion history outside its native range in Europe.

Social disparities in women's health service use in the United States: a population-based analysis

PurposePoor and disparate reproductive health outcomes in the United States may be related to inadequate and differential receipt of women's health care. We investigated trends in and determinants of adult U.S. women's health service use, 2006–2010. MethodsWe analyzed population data from 7897 women aged 25–44 years in the National Survey of Family Growth from 2006 to 2010 using multivariable logistic regression. ResultsWomen's health service use in the past year was reported by 74% of the sample. Among noninfertile, sexually active women, 47% used contraceptive services; fewer used pregnancy (21%) and sexually transmitted infection (14%) services. In multivariable models, the odds of service use were greater among older, poor, unemployed women and women with less educational attainment than younger and socioeconomically advantaged women. Black women had greater odds of using pregnancy, sexually transmitted infection and gynecologic examination services than white women (odds ratio, 1.4–1.6). Lack of insurance was associated with service use in all models (odds ratio, 0.4–0.8). ConclusionsAlthough age-related differences in women's health service use may reflect fertility transitions, social disparities mirror reproductive inequalities among U.S. women. Research on women's health service use and outcomes across the reproductive life course and forthcoming sociopolitical climates is needed.

Reproductive Inequality in Canada

This article will examine the implications of taking an autonomy approach to reproductive health policy and practice, and the value of shifting to an equality approach. In legal terms, the acknowledgement that reproductive control is often a s. 15 equality matter, not simply a s. 7 concern, could lead to drastically different health care services. The author will begin by explaining R. v. Morgentaler (1988), the case which set the precedent that reproductive health is a s. 7 concern—that is, an autonomy matter. The author will identify some current conditions in the context of reproductive health in order to illustrate the shortcomings to s. 7. Specifically, she will demonstrate the importance that government take positive action rather than uphold a position of non-interference. The subsequent section will make a case for redressing present conditions via the invocation of s. 15 equality rights. The author will conclude with an evaluation of s. 15, considering the objection that not even this section can guarantee positive action.

Asian Ethnicity and Comparable Outcomes After Frozen Blastocyst Transfer

BACKGROUND: Several studies have demonstrated a disparity in pregnancy outcome when comparing Asian and Caucasian women undergoing fresh in vitro fertilization (IVF) cycles. Despite controlling for embryo quality, this reproductive inequality persisted, suggesting that endometrial factors may be responsible for the lower implantation rate. The objective of this study was to investigate whether this difference was seen after frozen blastocyst transfer.

Reproductive Inequality in Sub‐Saharan Africa: Differentials versus Concentration

Within developing countries, our understanding of reproductive inequality-how fertility is distributed within a population-has been shaped largely by studies of fertility differentials, a practical but partial-information measure. In this study, we examine whether exclusive reliance on differentials biases this understanding. Findings based on recent data from sub-Saharan Africa show bias. We find that historical and especially cross-country comparisons can yield substantially different conclusions about the magnitude and even the direction of inequality patterns and trends, depending on whether differentials or fuller-information measures are used. For instance, the fertility differentials associated with education have remained relatively stable as national fertility has fallen, but inequality (as calculated by a fuller measure) has increased. Such results underscore the value of complementing existing studies of fertility differentials with analyses based on fuller-information measures. The analyses also show how change in differential fertility behavior and in the educational composition of national populations has shaped recent variations in reproductive inequality in the region.

KIN SELECTION, LOCAL COMPETITION, AND REPRODUCTIVE SKEW

In a spatially structured population, limited dispersal gives rise to local relatedness, potentially favoring indiscriminate helping behavior. However, it also leads to local competition, which reduces the benefits of helping local kin. This tension has become the focus for a growing body of theoretical work. Existing models, however, have focused chiefly on the net impact of limited dispersal on cooperative or competitive effort in a homogeneous population. Here, I extend existing models of kin selection in a group-structured population to allow for asymmetries in expected fecundity and reproductive success among group members. I explore the consequent impact of limited dispersal on the evolution of helping and harming behavior, and on the degree of reproductive inequality or skew. I show that when individuals in a group differ in their expected fecundity, limited dispersal gives rise to kin selection for harming behavior on the part of more fecund individuals, and for helping behavior on the part of less fecund individuals. As a result, philopatry tends to exaggerate differences in reproductive success, and so promotes greater reproductive skew.

Interactions between arbuscular mycorrhizal fungi and intraspecific competition affect size, and size inequality, of Plantago lanceolata L.

Summary 1 Intraspecific competition causes decreases in plant size and increases in size inequality. Arbuscular mycorrhizas usually increase the size and inequality of non-competing plants, but mycorrhizal effects often disappear when plants begin competing. We hypothesized that mycorrhizal effects on size inequality would be determined by the experimental conditions, and conducted simultaneous field and glasshouse experiments to investigate how AM fungi and intraspecific competition determine size inequality in Plantago lanceolata . 2 As predicted, plant size was reduced when plants were competing, in both field and controlled conditions. However, size inequality was unexpectedly reduced by competition. Plants may have competed in a symmetric fashion, probably for nutrients, rather than the more common situation, in which plant competition is strongly asymmetric. 3 Mycorrhizas had no effect on plant size or size inequality in competing plants in either field or controlled conditions, possibly because competition for nutrients was intense and negated any benefit the fungi could provide. 4 The effects of mycorrhizas on non-competing plants were also unexpected. In field-grown plants, AM fungi increased plant size, but decreased size inequality: mycorrhizal plants were more even in size, with few very small individuals. In glasshouse conditions, mycorrhizal colonization was extremely high, and was generally antagonistic, causing a reduction in plant size. Here, however, mycorrhizas caused an increase in size inequality, supporting our original hypothesis. This was because most plants were heavily colonized and small, but a few had low levels of colonization and grew relatively large. 5 This study has important implications for understanding the forces that structure plant communities. AM fungi can have a variety of effects on size inequality and thus potentially important influences on long-term plant population dynamics, by affecting the genetic contribution of individuals to the next generation. However, these effects differ, depending on whether plants are competing or not, the degree of mycorrhizal colonization and the responsiveness of the plant to different colonization densities.

CO2 enrichment reduces reproductive dominance in competing stands of Ambrosia artemisiifolia (common ragweed)

Plants growing in dense stands may not equally acquire or utilize extra carbon gained in elevated CO(2). As a result, reproductive differences between dominant and subordinate plants may be altered under rising CO(2) conditions. We hypothesized that elevated CO(2) would enhance the reproductive allocation of shaded, subordinate Ambrosia artemisiifolia L. (Asteraceae) individuals more than that of light-saturated dominants. We grew stands of A. artemisiifolia at either 360 or 720 muL L(-1) CO(2) levels and measured the growth and reproductive responses of competing individuals. To test whether elevated CO(2) altered size and reproductive inequalities within stands, we compared stand-level coefficients of variation (CV) in height growth and final shoot, root, and reproductive organ biomasses. Elevated CO(2) enhanced biomass and reduced the CV for all aspects of plant growth, especially reproductive biomass. Allocation to reproduction was higher in the elevated CO(2) than in the ambient treatment, and this difference was more pronounced in small, rather than large plant positive relationships between the CV and total stand productivity declined under elevated CO(2), indicating that growth enhancements to smaller plants diminished the relative biomass advantages of larger plants in increasingly crowded conditions. We conclude that elevated CO(2) stimulates stand-level reproduction while CO(2)-induced growth gains of subordinate A. artemisiifolia plants minimize differences in the reproductive output of small and large plants. Thus, more individuals are likely to produce greater amounts of seeds and pollen in future populations of this allergenic weed.

Szegénység, marginalizáció, szegregáció. Adalék a társadalmi egyenlőtlenségek értelmezéséhez

A szerző bemutatja és elemzi a szegénység(politikák) nemzetközi, különösen kelet-európai jellemzőit, a tipikus magyarországi társadalmi periféria folyamatokat, szociális kihívásokat. Az elemzés során bizonyítja, hogy a szegénység nemzeti, regionális, etnikai és nemi sajátosságokkal is bír. Magyarországon belül is jelentős területi szegénység differenciák tapasztalhatók, s a rendszerváltozás óta eltelt másfél évtizedben a rétegződési legyező is szétnyílt. A tanulmány többek között megállapítja, hogy a társadalomból való kizáródás fő okai a szegénység, az újratermelődő egyenlőtlenségek, az etnikai, nemi, kor szerinti vagy vallási diszkrimináció, a kulturális hiányok, a munkanélküliség, s mindezekből következően a munka és hajlék nélkül maradtak számának növekedése, a kapcsolati rendszerek szétzilálódása, majd megszűnése. Több, friss empirikus vizsgálat eredményeit feldolgozva bizonyítja továbbá, hogy a hasonló társadalmi helyzetű cigány és nem cigány népesség helyzete között ma is jelentős, jellemzően a roma népesség halmozott hátrányait nyomatékosító és tartósító tendenciák érvényesülnek.

DESCRIBING INEQUALITY IN PLANT SIZE OR FECUNDITY

Lorenz curves have been used to describe inequality in plant size and fecundity, where the total inequality is summarized by the Gini coefficient. Here we propose a second and complementary statistic, the Lorenz asymmetry coefficient, which characterizes an important aspect of the shape of a Lorenz curve. The statistic tells us which size classes contribute most to the population's total inequality. This may be useful when interpreting the ecological significance of plant size or reproductive inequality.

Describing Inequality in Plant Size or Fecundity

Lorenz curves have been used to describe inequality in plant size and fecundity, where the total inequality is summarized by the Gini coefficient. Here we propose a second and complementary statistic, the Lorenz asymmetry coefficient, which characterizes an important aspect of the shape of a Lorenz curve. The statistic tells us which size classes contribute most to the population's total inequality. This may be useful when interpreting the ecological significance of plant size or reproductive inequality.

Size and Reproductive Inequality in Mycorrhizal and Nonmycorrhizal Populations of Abutilon Theophrasti

1 We grew Abutilon theophrasti Medic. with and without mycorrhizal colonization in the field at two plant densities both of which resulted in self-thinning of the populations. 2 There was an initial convergence of plant density from high and low sowing densities to a common density of plants. Thereafter, for both sowing densities log biomass increased and log density decreased along a biomass-density boundary that had a slope of during the period of greatest density-dependent mortality. 3 Size inequality among individuals decreased during the period of greatest densitydependent mortality because of greater mortality in the smallest size classes. 4 For the first 92 days, mycorrhizal colonization did not significantly alter the biomass-density relationship. 5 Mycorrhizal populations did not develop significantly different size inequality than nonmycorrhizal populations, but they did develop significantly greater inequality in fecundity. The proportion of individuals reaching reproductive maturity was similar in the two populations, but reproductive individuals in mycorrhizal populations had more capsules than those in nonmycorrhizal populations.

Reproductive Hierarchies in Erodium: Effects of Variation in Plant Density and Rainfall Distribution

Reproductive hierarchies in even—aged plant monocultures often reflect the dynamics of intraspecific competition and, by their influence on effective population number, can alter significantly the relative importance of genetic drift in the evolution of plant populations. In experimental populations of Erosium boytrs and E. brachycarpum, I examined the interactive effects of intraspecific competition and rainfall variability on the development of reproductive hierarchies in these annual species. Reproductive inequality within monocultures of both species increased with increasing plant density and plant productivity, as measured by seed production, was determined by rainfall distribution. The magnitude of reproductive inequality was dependent on the interaction of sowing density, reproductive inequality was greatest in populations that experienced early autumn precipitation and lowest in populations exposed to drought during flowering. In contrast, at the lowest sowing density there was no significant effect or rainfall pattern on reproductive inequality. Effective population number was relatively insensitive to increases in population density because of increased inequality in reproduction at higher population densities. Reproductive variance could be a major contributor to drift variance in dense populations of both Erodium species.

Genetic Sampling in a Random Mating Population of Constant Size and Sex Ratio

An expression is derived for the effective breeding size of a random mating population of constant size and sex ratio, which takes into account reproductive inequalities among the breeding individuals. Consideration is given to the problem of estimating the possible genetic drift in the mean of a given quantitative character in an experimental control population.