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PubMed2004

Real and perceived threats to reproductive health: a way forward.

Ten years ofter the International Conference on Population and Development finds the reproductive health community under threat from at least three sources: global initiatives, reforms of the health sector, and new financial modalities from donors and lenders. These challenges, however, mainly reflect the complete system failure in many low-income countries in providing basic reproductive health services to women, especially those who are poor and socially vulnerable. The reproductive health community can do a lot more to address the system failures and potential threats and take advantage of opportunities offered. The starting point should be an internal look at how the reproductive health community has performed in helping low-income countries. Understanding these changes and opportunities in the health sector is another important step, but understanding will only be effective if representatives of the reproductive health community in low-income countries are armed with the skills and tools needed to engage in health sector reforms, to take advantage of global initiatives and to effectively influence the implementation of new holistic forms of aid.

Developing Countries↗
PubMed2003

Phylogeny and evolution of reproductive modes in Autolytinae (Syllidae, Annelida).

The phylogeny of 31 autolytine taxa (Syllidae, Polychaeta, and Annelida) was estimated based on 16S rDNA and 18S rDNA sequences. Outgroups included 12 non-autolytine syllids and four other annelids from related groups. The phylogeny was used to trace the evolution of the various reproductive strategies (i.e., epigamy, anterior and posterior scissiparity, and gemmiparity) within the group, and it will also serve as a basis for a forthcoming revision of autolytine taxonomy. The two genes were analysed both separately and in combination using parsimony, maximum likelihood, and Bayesian inference. Regardless of method used the combined analysis supported a division of Autolytinae into three major clades: one with epigamous Autolytus; a second comprising Autolytus and Myrianida with posterior scissiparity and gemmiparity; and a third containing Proceraea, Procerastea, and Virchowia with anterior scissiparity. The relationship between these three groups is uncertain. Ancestral reproductive states were reconstructed with parsimony and maximum likelihood, and the results unequivocally support epigamy as the plesiomorphic reproductive mode in Syllidae, and that schizogamy in Syllinae and Autolytinae are separate events. The evolution of reproductive traits is ambiguous within Autolytinae, and either of the different reproductive modes could represent the ancestral state.

Animals↗
PubMed2005

The ethics of human reproductive cloning.

This article addresses the question of whether human reproductive cloning could be ethically justifiable in at least some cases involving infertile couples who would choose cloning as a way to have a genetically related child. At present, the risk of congenital anomalies constitutes a compelling argument against human reproductive cloning. The article explores whether reproductive cloning could be ethically justifiable if, at some future time, cloning becomes possible without an elevated risk of anomalies. It is argued that freedom to use cloning is a form of procreative freedom and, as such, deserves respect. All of the objections that have been raised against human reproductive cloning fall under three main categories: those that appeal to the interests of the child, those based on consequences for society, and those arising from teleological views. Objections that appeal to the child's interests are, in turn, of two main kinds: consequentialist and deontological. All of these types of objections are examined, and it is found that each involves serious problems that prevent it from being a reasonable objection in the context of the infertility cases considered. It is concluded that human reproductive cloning would be ethically justifiable in at least some cases involving infertile couples, provided that it could be performed without an elevated risk of anomalies.

Child↗
PubMed2002

Reproductive strategies for human survival.

Reproductive strategies for the human species have basically remained unaltered since Homo sapiens first appeared, probably in the valleys of Africa: males have always attempted to pass their genes to the largest feasible number of females, selecting those females capable of providing the best quality of oocytes; females invariably have sought a male capable of providing the best means of survival for herself and her offspring. This meant that human sexuality has been essentially conceptive, although it is reasonable to suppose that it began to lose this 'exclusive' connotation early in the cultural evolution of the species. Then, during the 20th century, major revolutions occurred: first, with the advent of contraception, sex without reproduction became a reality; then, with assisted reproduction technology, humans devised reproduction without sex; finally, very recently, women have begun to reproduce even in menopause. Additional strategies will, no doubt, soon be available, although we cannot as yet clearly see whether, or when, reproduction without sex and gametes, or in-vitro gestations will become available.

Humans↗
PubMed2003

Epidemiological transitions, reproductive health, and the Flexible Response Model.

In concert with improving standards of living since the mid-19th century, chronic and non-infectious diseases replaced infectious diseases as the major causes of mortality in more developed countries. Thus, economic development has been seen as one strategy to improve women's reproductive health. However, rates of two of the major contributors to women's illness, maternal mortality and breast cancer, do not correspond well with the level of economic development. Drawing upon our longitudinal study of reproductive functioning among rural Bolivians (Project Reproduction and Ecology in Provincia Aroma (REPA)), we propose an evolutionary model to explain variation in certain aspects of women's reproductive health. Our findings suggest new avenues of inquiry into the determinants of reproductive health and have implications for improving the well-being of women worldwide.

Bolivia↗
PubMed1995

Comparative effects of mites and lice on the reproductive success of rock doves (Columba livia).

We report experimental data comparing the effects of Mesostigmatid mites and Ischnoceran lice on the reproductive performance of a single group of captive rock doves (Columba livia). Several components of host reproductive success were compared for the two groups, including number of eggs laid, hatching success, nestling growth rates, fledging success, post-fledging body mass and survival. Adult body mass and survival were also compared. There was a dramatic difference in the effects of the mites and lice. The former drove host reproductive success to zero, mainly by agitating adults and causing them to incubate eggs less faithfully. Nestling growth rates and post-fledging survival were also significantly reduced by mites. Lice showed no effect on reproductive success whatsoever, even though the feather damage they cause is known to have energetic consequences (Booth, Clayton & Block, 1993). Neither parasite had a significant effect on adult birds. Although Ischnocera are found on most species of birds, our results for lice constitute the first experimental test of the impact of Ischnocera on avian reproductive success (preliminary report by Clayton & Tompkins, 1994). We discuss reasons for the different effects of mites and lice, including the relationship of horizontal (mites) and vertical (lice) transmission to the evolution of virulence.

Animals↗
PubMed2003

An experimental study of the reproductive success of Echinostoma friedi (Trematoda : Echinostomatidae) in the golden hamster.

Viable eggs produced weekly per infective stage was used as a measure of the reproductive success of Echinostoma friedi during the first 12 weeks of infection in hamsters. The weekly reproductive success was not constant during the experiment in relation to the egg output and the proportion of viable eggs produced. The egg release started during week 2 post-inoculation, attaining a maximum during week 3. A decline in egg output was observed from week 9. Viable eggs were only produced from week 3 post-inoculation and a maximum was attained at week 4 of the experiment. A decline in egg viability was observed from week 9. Considering together the egg output and the egg viability, the maximum weekly reproductive success was obtained during week 4 post-inoculation. The changes in the weekly reproductive success were not reflected in variations in worm numbers and body sizes during the course of the infection. The humoral immune response of golden hamsters during the infection with E. friedi was determined. Increases of IgG levels against somatic and excretory/secretory products of E. friedi were detected coinciding with the reduction in the reproductive success.

Animals↗
PubMedDate not supplied

Issues to consider in operationalizing reproductive health.

The International Conference on Population and Development (ICPD) served as the international launchpoint for a broadened reproductive health agenda, bringing global attention to a variety of underlying issues that impact on women's health and well-being, and highlighting the need to redress imbalances in gender equity that have had negative health and social consequences in particular for women and girls. To meet the challenges of the ICPD, programs must assess, prioritize and implement an expanded set of reproductive health interventions within an environment of diminishing resources. This paper argues that hidden social and health costs that particularly affect women must be included in the assessment and prioritization of reproductive health interventions. In addition, it argues that issues of gender and sexuality cannot be separated from the delivery of appropriate family planning and reproductive health care if we are to have a significant impact on improving the reproductive health of current and future generations.

Family Planning Services↗
PubMedDate not supplied

Breaking the mold: expanding options for reproductive health awareness: the CARE experience.

The early years of the CARE family planning and reproductive health program were geared primarily toward modern methods of contraception and providing services. However, new and fresh opportunities to address reproductive health awareness and natural family planning are now emerging as important options. In these programs, coordination and collaboration with other sectors such as food and nutrition, children's health and natural resource management, combined with more sophisticated approaches for assessing need and reaching communities with information, has resulted in more people being reached than ever before with appropriate options and opportunities for reproductive health awareness and care. There are examples of CARE projects from India, Peru and Nepal where activities which feature working across development sectors and engaging communities to address their individual and collective RH needs are featured. Ways to disseminate information about reproductive health are being broadened to include creative combinations of interpersonal, mass and folk media', whether it be an informal one-to-one counseling session with flipcharts, a community mobilization event, a multi-media campaign, or any combination thereof. Likewise, the target audience need not always be the women of reproductive age, not should the RH messengers always be the medical and public health professionals. What is critical in all of these instances is to craft strategies based on appropriate research and need, continuously monitor progress, refine approaches as necessary, track results and evaluate the process and impact of interventions leading to behavior change. The challenge is not insignificant, but the rewards to be reaped through the improved programs are clearly worth striving for.

Awareness↗
PubMed2001

The effects of low levels of pollutants on the reproduction of golden eagles in western Norway.

The reproductive success of golden eagles was studied in an area in western Norway between 62 degrees and 63 degrees N between 1973 and 1999. Addled eggs were collected for analysis of chemical pollutants from nine territories; five from coastal areas and four from inland. The coastal sites had lower annual reproductive output than inland sites, and the eggs had a higher content of organochlorine compounds. There were relatively strong negative correlations between reproductive output and (1) shell thickness and (2) DDE concentration in eggs. The data indicate that the golden eagle may be a particularly sensitive species to DDE. It is proposed that the higher organochlorine content found in the eggs of coastal birds was caused by a contribution of marine birds to the diet, as opposed to inland eagles which have a prey basis consisting almost entirely of terrestrial herbivores such as grouse, mountain hare and cervids. Our data-set on reproductive output is, however, too small to establish a general relationship between DDE contamination and reproductive output in golden eagles.

Animals↗
PubMed2004

Reproductive compatibility between mite populations previously identified as Euseius concordis (Acari: Phytoseiidae).

The objective of the present research is to study the reproductive compatibility between populations of predatory mites previously identified as Euseius concordis (Chant) based on morphological characteristics. Colonies of these mite populations were established in the lab with specimens collected from different localities and host plants. Reproductive compatibility was evaluated through crosses and backcrosses within and between populations and the subsequent observation of females' oviposition, over a period of 10 days. The levels of oviposition obtained in the crosses between individuals from the same population were higher than those obtained in the crosses between individuals from different populations. Results indicate the occurrence of post-mating reproductive incompatibility between the mite population from Petrolina and the other populations studied. Crosses and backcrosses between populations involving female mites from Petrolina did not produce offspring, although endospermatophores were present inside the spermathecas of those females. Oviposition was reduced, and only sons were obtained, in crosses between populations with males from Petrolina. Crosses of females from Pontes e Lacerda and males from Jaguariúna and vice versa produced only male progeny. Our results established that the populations originating from Arroio do Meio, Pontes e Lacerda, Jaguarúna and Viçosa, are reproductively compatible. However, the latter populations and the population from Petrolina are genetically isolated. Based on these results we suggest that more cytological and genetic studies are needed to establish if this reproductive isolation represents a species barrier.

Animals↗
PubMed2004

The nature of genetic variation in sex and reproduction-related genes among sibling species of the Drosophila melanogaster complex.

Much is known about the biology of Drosophila melanogaster. As a model organism, a comprehensive understanding of its development, physiology and reproduction has been acquired. As a result, a broad variety of transferable genetic tools and information has allowed sibling species of the D. melanogaster complex to emerge as an important speciation model system. By comparing D. melanogaster with its close relative, Drosophila simulans, as well as its other sibling species, we are beginning to understand the nature of genetic changes during the early stages of speciation. In general, we find that genes and traits involved in sex and reproduction are more variable. A large assortment of genes and traits that are involved in various aspects of mating and fertility reveal diagnostic differences between these sibling species. Sex and reproduction-related (SRR) genes are, on average, more diverged than genes with no apparent reproductive function. Furthermore, SRR genes appear more permissive at opting in novel function. These results follow a general trend observed in other taxa and demonstrate the preferential involvement of SRR genes in reproductive isolation and species formation.

Animals↗
PubMedDate not supplied

Basal metabolic rate and energetics of reproduction in therian mammals.

Traditionally, the fact that reproduction in eutherian (= placental) mammals tends towards prolonged intrauterine development and short lactation has been interpreted as an evolutionary advance over the metatherian (= marsupial) short gestation and prolonged lactation. However, it has recently been postulated that marsupial reproduction involves low initial energy investment and may be advantageous by minimizing energy loss if conditions necessitate early termination. Moreover, because marsupials have basal metabolic rates (BMRs) 30% lower than those of most eutherians, it has been suggested that daily and total energy expenditures during reproduction may also be lower. We have now tested the predictions that low BMR is maintained during reproduction and that initial investment is lower in marsupials. Using indirect calorimetry, we have made the first longitudinal measurements of energy expenditure during reproduction for a marsupial and for two eutherian species with low BMRs. We find that initial investment is lowest in a eutherian and total energetic expenditures were greatest for the marsupial. We also find that, relative to BMR, all three species have increased mean maternal resting metabolic rates (RMRs) during both gestation and lactation; this is the first evidence that mammals with low BMRs can substantially elevate metabolism for prolonged periods during gestation and lactation.

Animals↗
PubMed2000

Adaptive plasticity in mate preference linked to differences in reproductive effort.

There is abundant evidence for the existence of marked mate preferences in natural populations, but the occurrence of within-population variation in mate preferences has received little attention and is often regarded as nonadaptive deviation from the optimal norm. Here we show experimentally that the preference of female collared flycatchers Ficedula albicollis for male forehead patch size, a sexually selected trait, varies with the time of breeding, an environmental factor with strong effects on reproductive success. Contrary to expectations based on time-constrained choice models, only late-breeding females prefer males with a large patch size. The variation in mate preference matches a seasonal change in female reproductive success: long-term data reveal a positive relationship between female reproductive success and male patch size exclusively in late breeders. In addition, female reproductive effort, as assessed by clutch size, appears to be adjusted relative to both timing of breeding and male phenotype. We conclude that not only can mate preferences display adaptive plasticity within populations, but this plasticity can also be linked to differences in reproductive investment.

Adaptation, Physiological↗
PubMed1996

Menstrual and reproductive factors and risk of breast cancer in Asian-Americans.

We conducted a population-based case-control study of breast cancer among Chinese-, Japanese- and Filipino-American women in Los Angeles County Metropolitan Statistical Area (MSA), San Francisco-Oakland MSA and Oahu, Hawaii. One objective of the study was to quantify breast cancer risks in relation to menstrual and reproductive histories in migrant and US-born Asian-Americans and to establish whether the gradient of risk in Asian-Americans can be explained by these factors. Using a common study design and questionnaire in the three study areas, we successfully conducted in-person interviews with 597 Asian-American women diagnosed with incident, primary breast cancer during the period 1983-87 (70% of those eligible) and 966 population-based controls (75% of those eligible). Controls were matched to cases on age, ethnicity and area of residence. In the present analysis, which included 492 cases and 768 controls, we observed a statistically non-significant 4% reduction in risk of breast cancer with each year delay in onset of menstruation. Independent of age at menarche risk of breast cancer was lower (odds ratio; OR=0.77) among women with menstrual cycles greater than 29 days. Parous Asian-American women showed a significantly lower risk of breast cancer then nulliparous women (OR=0.54). An increasing number of livebirths and a decreasing age at first livebirth were both associated with a lower risk of breast cancer, although the effect of number of livebirths was no longer significant after adjustment for age at first livebirth. Women with a pregnancy (spontaneous or induced abortions) but no livebirth had a statistically non-significant increased risk (OR=1.84), but there was no evidence that one type of abortion was particularly harmful. A positive history of breastfeeding was associated with non-significantly lower risk of breast cancer (OR=.78). There are several notable differences in the menstrual and reproductive factors between Asian-Americans in this study and published data on US whites. US-born Asian Americans had an average age at menarche of 12.12 years-no older than has been found in comparable studies of US whites, but 1.4 years earlier than Asian women who migrated to the US. Asian-American women, particularly those born in the US and those who migrated before age 36, also had a later age at first birth and fewer livebirths than US whites. A slightly higher proportion of Asian-American women breastfed, compared with US whites. The duration of breastfeeding was similar in US-born Asians and US whites, but was longer in Asian migrants, especially those who migrated at a later age. Menstrual and reproductive factors in Asian-American women are consistent with their breast cancer rates being at least as high as in US whites, and they are. However, the effects of these menstrual and reproductive factors were small and the ORs for migration variables changed only slightly after adjustment for these menstrual and reproductive factors. These results suggest that the lower rates of breast cancer in Asians must be largely as a result of other environmental/lifestyle factors.

Adult↗
PubMed2002

Genetic divergence and reproductive isolation in the Ochthebius (Calobius) complex (Coleoptera: Hydraenidae).

The reproductive isolation in hydrenid beetles of the Ochthebius complex was studied by analysing gene exchange in natural populations of O. quadricollis, Ochthebius sp. A and O. brevicollis steinbuehleri collected along the Mediterranean coasts. The ranges of these three species are largely allopatric, but sympatric areas were detected between contiguous taxa, ie, O. quadricollis and Ochthebius sp. A; Ochthebius sp. A and O. b. steinbuehleri. Three levels of reproductive isolation and genetic divergence were observed. One level involves extensive intraspecific genetic divergence within the biological species O. quadricollis, Ochthebius sp. A and O. brevicollis, associated with both physical barriers (eg, sea and sand stretches) and the low dispersal capacity of larvae and adults. The finding of transitional samples between the most differentiated population groups should indicate, however, that there is still some gene flow between the populations of the three taxa. Another level is found between Ochthebius sp. A and O. b. steinbuehleri, whose gene pools appear to be fairly distinct in spite of the fact that reproductive isolation is still incomplete: in their few syntopic sites, some F1 hybrids appeared indeed to have lower fitness, since backcrosses or recombinant genotypes were never observed. The final level in the evolution of reproductive isolation (full reproductive isolation) has been achieved by the species O. quadricollis and Ochthebius sp. A. No F1 or F(n) hybrids, nor backcrosses were found in their sympatric areas. The relative importance of ecological factors and evolutionary forces in the prevention of gene exchange between taxa are discussed.

Alleles↗
PubMed2004

Physiological predictors of reproductive outcome and mother-infant behaviors in captive rhesus macaque females (Macaca mulatta).

Previous research has shown that offspring of females with low cerebrospinal fluid (CSF) 5-hydroxyindoleacetic acid (5-HIAA) concentrations are less likely to survive the first year of life than are offspring of females with high CSF 5-HIAA concentrations. In addition, studies of free-ranging rhesus macaque males have suggested that individuals with low CSF 5-HIAA concentrations suffer reduced reproductive success relative to their high serotonin counterparts. We examined CSF concentrations of the monoamine metabolites 5-HIAA and homovanillic acid (HVA), and plasma cortisol concentrations as predictors of first-time adult reproductive potential, maternal behavior, and overall social interactions in two groups of captive female rhesus macaques and their first offspring. Repeated CSF and blood samples were obtained from adult females in two social groups, and focal observations were performed for both new mothers and infants during the first month following parturition. We found that the reproductively aged nulliparous females who failed to give birth to their first offspring showed significantly lower CSF 5-HIAA concentrations than those females who gave birth. Among those females that gave birth to offspring, females with low CSF 5-HIAA concentrations and females with high plasma cortisol concentrations were overly protective and restrictive with their infants. CSF HVA concentration was not associated with reproductive output, social behavior, aggression, or mother-infant interactions in this sample of rhesus macaque females. We conclude that low CNS serotonin activity and high stress, measured by high plasma cortisol, are correlated with reduced reproductive success and patterns of high maternal restrictiveness in young adult female rhesus macaques.

Aggression↗
PubMed2002

Male reproductive competition in spawning aggregations of cod (Gadus morhua, L.).

Reproductive competition may lead to a large skew in reproductive success among individuals. Very few studies have analysed the paternity contribution of individual males in spawning aggregations of fish species with huge census population sizes. We quantified the variance in male reproductive success in spawning aggregations of cod under experimental conditions over an entire spawning season. Male reproductive success was estimated by microsatellite-based parentage analysis of offspring produced in six separate groups of spawning cod. In total, 1340 offspring and 102 spawnings distributed across a spawning season were analysed. Our results show that multiple males contributed sperm to most spawnings but that paternity frequencies were highly skewed among males, with larger males on average siring higher proportions of offspring. It was further indicated that male reproductive success was dependent on the magnitude of the size difference between a female and a male. We discuss our results in relation to the cod mating system. Finally, we suggest that the highly skewed distribution of paternity success observed in cod may be a factor contributing to the low effective population size/census population size ratios observed in many marine organisms.

Animals↗