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Unsafe abortions and their complications are a major cause of maternal mortality. Hospital based studies from most African countries confirm that up to 50% of maternal deaths are due to abortion. This paper reviews problem of induced abortion in sub-Saharan Africa. Issues of prevalence and prevention are addressed while acknowledging the need to review the legal regimes operating in these countries.
Data from an urban obstetrics clinic on 291 unmarried women with a current unplanned pregnancy show that women with only one partner in the past year are older and are more likely to use the most effective contraceptive methods than are women who have more than one partner. Women with only one partner are also more likely to be solely responsible for decision-making about the choice of contraceptive methods, and are not as likely to use drugs in conjunction with sex. However, women with one partner are also less likely than others to use condoms or to protect in some other way against sexually transmitted diseases or the human immunodeficiency virus.
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The thalassemia syndromes were the first of human diseases to become thoroughly examined for the underlying molecular lesions by the application of molecular genetic strategies and recombinant DNA methods. Students of thalassemia have now enjoyed over two decades of experience with this research paradigm. These experiences reveal both the awesome power and the limitations of the "reductionist, deterministic" approach of gene cloning and analysis. Incredibly precise and abundant information about the exact molecular lesions responsible for various forms of thalassemia were rapidly obtained by the use of molecular genetic approaches. The mechanisms by which these mutations deranged globin gene expression could be documented with extraordinary precision and efficiency. Precise, powerful methods for detecting disease early in fetal life were rapidly developed, made practical for field use, and disseminated widely. This resulted in a dramatic reduction in the incidence of new births of patients with homozygous beta thalassemia. These experiences demonstrate the extraordinary impact that recombinant DNA technology has upon our ability to understand disease processes, to detect disease long before its phenotypic expression is apparent, and to influence the prevalence of the abnormal alleles in the population. Experience with the antenatal diagnosis of the thalassemias also demonstrates, and should alert us to, the relative ease with which genetic information can be applied to societal and governmental initiatives to alter the reproductive behavior of individuals. While the benefits of reducing the incidence of beta thalassemia are clearcut, application of the strategies that were applied in this narrow situation to broader aspects of disease or genetic manipulation does raise concerns. The thalassemia syndromes demonstrate that genetic information does have more than a theoretical potential to have a major impact upon society. The struggles of many investigators to develop effective pharmacologic agents for the treatment of hemoglobinopathies have also revealed some of the limitations of an isolated molecular approach to the understanding of disease. The tortuous course by which a class of reagents has been identified for stimulation of HbF synthesis illustrates an important point. The application of recombinant DNA methods revealed an entirely new array of pathophysiologic facts that stimulated new hypotheses about the regulation of gene expression and opportunities to manipulate that regulation therapeutically. However, practical application and proper understanding of the molecular information were achieved only when those data were placed in the context of cell biology, tissue and organ-based clinical pathophysiology, and clinical pharmacology. Progress was possible only because of the productive interaction of talented individuals with expertise in these different fields. Our two decades of experience with the thalassemias illustrate very clearly the fact that biology and disease are extraordinarily complex, non-deterministic processes. They will be understood and treated properly only if thriving centers exist within which individuals with diverse interests, expertise, and perspectives about basic science and clinical medicine can exist, interact, and have sufficient time to employ their imaginations to the fullest benefit.
About 50 studies based on the 1988 National Survey of Family Growth (NSFG) and a telephone reinterview conducted with the same women two years later provide continuing information about the fertility and health of American women. Among the findings of these studies are that black women have almost twice as many pregnancies as do white women (5.1 vs. 2.8), with nearly all of the difference being unintended pregnancies. Unwanted births increased between 1982 and 1988, particularly among less-educated, poor and minority women. This increase in the proportion of unwanted births may have prompted the increase in female sterilization among these groups. Concern with the AIDS epidemic led to increases in condom use between 1982 and 1990, especially among the partners of teenagers and college-educated women. Rates of teenage pregnancy were fairly stable during the period 1980-1988, as increases in the proportion of teenagers having intercourse were offset by increases in condom use. Rates of infertility did not change significantly in the 1980s, but because of delayed childbearing and the aging of the baby-boom cohort, the number of older childless women increased substantially. The 1995 NSFG was redesigned in a number of ways in order to answer a new generation of questions about fertility and women's health in the United States.
Welfare reform programs currently being considered and implemented by the federal government and the states pose serious risks to poor women's health. Many of the proposed reforms, such as inflexible work requirements and time limits that threaten to reduce or eliminate current benefits, will make it more difficult for women to leave abusive relationships and will exacerbate the risks associated with violence against women. Other proposals target women's reproductive behavior. Programs that, for example, deny welfare benefits to teen mothers or to children born to women on welfare, increase the emotional stress experienced by poor pregnant women and may effectively coerce some women to seek abortions they would not otherwise choose. Benefit cuts also exacerbate the well-documented ill effects of poverty on children and families. The goals of welfare reform-increasing work participation and reducing poverty-can be more effectively achieved by means that do not pose these serious health risks to poor women.
In the male quail forebrain, aromatase-immunoreactive (ARO-ir) elements are clustered within the sexually dimorphic medial preoptic nucleus (POM), nucleus striae terminalis (nST), nucleus accumbens (nAc), and ventromedial and tuberal hypothalamus. These ARO-ir cells are sensitive to testosterone and its metabolites: Their number and size increase after exposure to these steroids. The POM and lateral septum are also characterized by a dense vasotocinergic innervation that is also sensitive to testosterone. We analyzed here the anatomical relationships between ARO-ir elements and VT-ir fibers in the quail prosencephalon. Sequential staining for vasotocin, aromatase, or vasotocin plus aromatase was performed on adjacent 30-microm-thick cryostat sections. High concentrations of thin VT-ir fibers were observed within the POM, nST, lateral septum, periventricular mesencephalic central gray, and ventromedial and tuberal hypothalamus. There was a close correspondence between the extension of the ARO-ir cells and of VT-ir fibers. In double-labeled sections, all clusters of ARO-ir cells with the exception of those located in the nAc were embedded in a dense network of VT-ir fibers. Many of the VT-ir terminals appeared to end in the neuropile surrounding ARO-ir elements rather than directly on their cell bodies. This study supports the idea that the testosterone-dependent aromatase system is directly innervated by a testosterone-dependent peptidergic system. Aromatase-containing cells could therefore be modulated by steroids both directly and indirectly through the vasotocin system. Alternatively, this neuroanatomical arrangement may mediate the control of vasotocin synthesis or release by steroids. Functional studies demonstrate that both aromatase and vasotocin affect reproductive behavior in quail, and the present data provide anatomical support for the integration of these effects.
In this review, the current information about the location of GnRH receptor protein and GnRH receptor mRNA in the rat central nervous system is summarized as well as the changes that occur in the GnRH receptor mRNA levels during different endocrine conditions of the animals. The results of these studies show that GnRH receptor protein and mRNA levels change in parallel in the hippocampus, suggesting that pretranscriptional factors control the synthesis of the receptor. In the arcuate and ventromedial nuclei of the hypothalamus, GnRH receptor mRNA levels are highest during the early morning of proestrus and during the morning of an estrogen-progesterone-induced LH surge. The timing of the changes in GnRH receptor mRNA levels indicates that increasing levels of estradiol are responsible for the increase in GnRH receptor synthesis. Binding of GnRH agonist to the brain GnRH receptor causes a dose-dependent increase in inositol phosphates as well as changes in intracellular Ca++ levels of the target neurons. Together, it is suggested that GnRH functions in the brain as a neurotransmitter and/or modulator linking the peripheral endocrine effects of GnRH to actions of the peptide inside the central nervous system where it can facilitate, for example, reproductive behaviors.
Data on 3,128 girls in grades eight, 10 and 12 who participated in the 1992 Washington State Survey of Adolescent Health Behaviors were used to analyze the association of a self-reported history of sexual abuse with teenage pregnancy and with sexual behavior that increases the risk of adolescent pregnancy. In analyses adjusting for grade level, respondents who had been sexually abused were 3.1 times as likely as those who had not been abused to say they had ever been pregnant; in multivariate analyses, respondents who had experienced abuse were 2.3 times as likely as others to have had intercourse but were not more likely than other sexually active respondents to have been pregnant. However, those with a history of sexual abuse were more likely to report having had intercourse by age 15 (odds ratio, 2.1), not using birth control at last intercourse (2.0) and having had more than one sexual partner (1.4). Thus, an association between sexual abuse and teenage pregnancy appears to be the result of high-risk behavior exhibited by adolescent girls who have been abused.
Data from a 1993-1994 survey of 150 black and Hispanic teenagers were used to examine differences in HIV risk-related behavior between young women who have a first sexual partner three or more years older than themselves and those whose first partner is their age. Compared with teenagers whose first partner had been roughly their age, the 35% of adolescents with an older partner had been younger at first intercourse (13.8 years vs. 14.6) and less likely to use a condom at first intercourse (63% vs. 82%). They also were less likely to report having used a condom at last intercourse (29% vs. 44%) or having used condoms consistently over their lifetime (37% vs. 56%) or in the previous six months (44% vs. 66%). Some 38% of teenagers with an older first partner had ever been pregnant, compared with 12% of those with a peer-age first partner. The mean number of partners and history of sexually transmitted diseases did not differ between the two groups.
An analysis of the economic benefits of adolescent contraceptive use utilizes information from a national private payer database and from the California Medicaid program to compare private- and public-sector costs and savings. The study estimates the costs of acquiring and using 11 contraceptive methods appropriate for adolescents, treating associated side effects, providing medical care related to an unintended pregnancy during method use and treating sexually transmitted diseases (STDs) and compares them with the costs of using no method. The average annual cost per adolescent at risk of unintended pregnancy who uses no method is $1,267 ($1,079 for unintended pregnancy and $188 for STDs) in the private sector and $677 ($541 for unintended pregnancy and $137 for STDs) in the public sector under the most conservative assumptions. At one year of use, private-sector savings from adolescent contraceptive use range from $308 for the implant to $946 for the male condom; public-sector savings rise from $60 for the implant to $525 for the male condom. Both the use of male condoms with another method and the advance provision of backup emergency contraceptive pills provide additional savings.
The neuropeptide cholecystokinin (CCK) is expressed in limbic system and hypothalamic nuclei that form a circuit that regulates the display of the female rodent reproductive behavior, lordosis. CCK mRNA and peptide levels fluctuate across the estrous cycle and have been shown to be modulated by estrogen exposure. The objective of these experiments was to examine the expression of CCK mRNA during postnatal development of this limbic-hypothalamic, lordosis regulating circuit, and to determine the age at which CCK mRNA expression becomes responsive to estrogen stimulation, by using quantitative in situ hybridization histochemistry. CCK mRNA levels were below the level of detectability within the circuit during the postnatal period, but increased during the peripubertal period. Rats were injected with either estradiol benzoate (EB), EB and progesterone, progesterone, or oil, and were killed 48 hours later on postnatal day (PND) 15, 20, and 25. Alternate brain sections were processed for CCK and preproenkephalin (PPE) mRNA in situ hybridization histochemistry. EB treatment induced CCK mRNA expression in the central portion of the medial preoptic nucleus and posterodorsal medial amygdala at PND 20 and 25, respectively. However, EB treatment increased PPE mRNA levels within the nuclei of the circuit at all ages examined. Progesterone had neither an independent nor additive effect on the EB induction of these neuropeptide messages. The estrogenic induction of CCK mRNA appears to be dependent on estrogen sensitive pathways of neurotransmission, or components of second messenger pathways which regulate CCK mRNA expression in the adult limbic-hypothalamic lordosis regulating circuit, which are not functional before PND 18-25.
The population in sub-Saharan Africa is growing faster than increases in food production, resulting in a net decrease in food production per capita. The Food and Agriculture Organization has stated that there is a "risk of widespread hunger" which could be prevented by "effective planning of water resources". However, the potential effects of such schemes on the human population are often inadequately assessed and the effect of large dams on human health is not clear. The potential risk to human health of water resources was emphasized a few years ago but no effective preventive programs were implemented, probably because of inadequate availability of information and lack of awareness. The effects on health of "large" water resource projects are not uniform within a population. Decision-makers have tended to focus on the positive effects, to obtain support for their plans. These include: 1) improvement in the well-being of the population (safe water more readily available, new infrastructure, better access to health care) and 2) increases in the food supply (more vegetables and fish available due to irrigation). Thus, there has been a logical expectation that more, better quality food will become available as a result of these schemes, whereas in fact, health and nutrition has often worsened, particularly in young children. Most of the diseases associated with water resource management are communicable, including diseases directly related to the presence of large quantities of water, such as: malaria, which increases in incidence immediately after the building of the dam, after which a new balance develops between the human population and the parasites, schistosomiasis, the disease which increases most in response to the building of dams, particularly in its most severe gastrointestinal form, diarrhea, as water is a major means of dissemination for many organisms, including those causing digestive tract infections and gastroenteritis (amebiasis, salmonellosis, cholera), due to poor sanitation, other parasitic infections, such as onchocerciasis and trypanosomiasis, which should be monitored as they may also threaten the population. Other communicable diseases may appear or increase in incidence with the influx of migrants to the irrigated area. Sexually-transmitted diseases and HIV infection are a particular problem. The large numbers of insects (mosquitoes, blackflies) may also have harmful effects on populations adapting to the new environment. These effects are related to each other and to the environmental changes. New types of food affect people's feeding habits and generate new sources of income. However, they may also lead to new and higher expenditure. There are also likely to be major socio-demographic changes associated with changes in reproductive behavior and women's activities. The location and nature of new homes and infrastructure (e.g. schools, health centers, roads) also contribute to the success or failure of the dam project. There are many constraints to be considered and a more comprehensive approach to the problem is required. Health and nutritional status may be used as simple indicators of the ability of the population to adapt to a new environment. This makes it possible to construct a causal model to identify the most effective and relevant areas of intervention. Health and nutrition issues are of vital importance and scientific findings should be used in decision-making processes for planning future large dam schemes.
BACKGROUND: This paper considers why antenatal care (ANC) programs for adolescents may need to be improved in areas where a high proportion of first pregnancies are to young girls. DESIGN: Descriptive data on the characteristics of 615 adolescents (aged 10-19 years) who attended for a first antenatal care visit at two rural hospitals in southern Malawi are given. For the 41.5% who came for a supervised delivery, details of their pregnancy care and delivery outcome are provided. The Chi-square test is used for determining significant differences between age and parity groups and logistic regression for an analysis of low birthweight. RESULTS: Fifty-two percent of girls were nulliparous, 24.5% were < or =16 years and 73.3% were illiterate. Prevalence of anemia, malaria and HIV infection was high. Girls who were nulliparous, illiterate, made early antenatal care visits or gave a history of stillbirth or abortion were less likely to attend for delivery. Few primiparae required an assisted vaginal delivery or cesarean section but primiparae had more adverse birth outcomes. Forty percent of primiparae <17 years gave birth to low birthweight babies as did 28.3% of multiparae. In a logistic regression (all adolescents) low birthweight was correlated with literacy (p=0.03) and number of antenatal care visits (p=0.01). CONCLUSIONS: Pregnancy morbidity and adverse birth outcomes were common in spite of antenatal care attendance. This partly reflects poor management of malaria during pregnancy. In areas like Malawi, where childbearing starts early, girls in their first pregnancy need good quality care and careful monitoring if problems are not to be perpetuated to a second pregnancy. Many girls start pregnancy with HIV and schistosomal infections which indicates the need for programs before girls become pregnant.
A study of the natural growth rate of the population using female cohorts by birth year has been carried out for the first time in our country. The study comprises 14 cohorts. The following characteristics are recorded: birth year, social group, educational level, number of live births, age of marriage, infant mortality rate, proto- and intergenetic intervals. Our report presents the key indicators of natural growth of population in the studied cohorts. A consistent trend of decreasing the number of livebirths is established. In the first studied cohort (1895-1899) the average number of offspring per woman is 3.94, reaching a level of 1.77 in the 1960-1964 cohort. The indicators for natural growth of population exhibit a similar trend. The summary fertility rate in the reference period decreases with more than 2 points--from 4.47 in 1895-1899 to 1.73 in 1960-1964. Likewise, the total reproduction rate goes down from 2.54 to 0.78 for the same period. Considerable changes have occurred in the indicators total period fertility rate and marriage fertility rate of women. For a period of 110 years the former has decreased 3.5 times, the latter--8 times. The drastic drop of the indicators of natural growth of the population is accounted for by an intricate complex of social, economic, psychological and biological factors. The marked aging of the population and the decrease of the percentage of women in active fertility age play a certain role in this process. The ascertained changes in the reproductive behavior and age structure of the female population are factors intensifying the unfavorable trends in the natural growth rate of the population in our country.
For any couple, the planning status of a pregnancy (what they intended, whether they used contraception, and whether they were successful) is strongly dependent on the planning status of their preceding pregnancy. The introduction of more acceptable and effective methods of fertility regulation has, however, attenuated the strength of these relationships. The patterns of continuity and change in planning status from pregnancy to pregnancy provide a parsimonious description of reproductive behavior over the course of the life cycle and of the major trends in planning in the recent past.
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