Effects of oral contraceptive use on body mass index and blood pressure among female villagers in north-east Thailand

The use of contraceptives has become prevalent among females in Thailand in the past 20 years, and oral contraceptive use has been suggested to trigger changes in fat intake, energy expenditure, fat metabolism and blood pressure. Based on field investigations of 391 married women aged 20 years or over in Yasothon Province, North-east Thailand, this study aims to elucidate the effects of oral contraceptive use on body mass index (BMI: kg/m2) and blood pressure, taking into account reproductive histories and socioeconomic conditions. The proportion of obese (BMI > or = 25) subjects was high in the age groups 30-39, 40-49 and 50-59, accounting for, respectively, 39.4%, 51.1% and 48.5% of these populations. The proportion of women with hypertension (90/140 mmHg) was 23.7%, 18.5% and 26.2% in the 40-49, 50-59 and 60-69 age groups. Current contraceptive practices in the studied population included sterilization by operation, oral contraception and injection. These methods accounted for 43.0%, 12.8% and 8.2% of the population, respectively. Sociodemographic factors such as reproductive history, years of education and household income were not significantly related to BMI or to blood pressure (ANOVA with age adjustment). In contrast, oral contraceptive users had significantly higher BMIs and diastolic blood pressures (p<0.01, ANOVA with age adjustment). Multiple regression analysis also revealed that oral contraceptive use was a weak but significant contributing factor to both high BMI and blood pressure when sociodemographic factors were taken into account and controlled for statistically. It can thus be concluded that the use of contraceptive pills, which contain oestrogen and progestin and are provided free of charge to Thai women, tend to increase BMI and to elevate blood pressure.     

A survey of family planning in the Philippines

A multicenter survey of 400 married Filipino women 15-40 years of age conducted in 1986 by Family Health International and the International Health Foundation provided valuable information on contraceptive use in the Philippines, as well as factors influencing such practices. The respondents, who were drawn from 10 urban communities in Metro Manila and 10 rural communities in Nueva Ecija Province, averaged 31.5 years of age and had a mean number of 2.9 children. 32% of respondents indicated they desired another child. 225 women (56%) reported they were using no method of contraception. 59 (14%) were protected from pregnancy by tubal sterilization or vasectomy. 77 women (19%) were oral contraceptive (OC) users, and 8 (2%) were IUD users. Only 1 respondent was using a long-acting contraceptive. 3 women used spermicides, 21 (5%) used condoms, 25 (6%) practiced rhythm, and 30 (3%) of the women's husbands practiced withdrawal. Overall, 27% of contraceptive users in this sample used more than 1 method. 26% had been using a contraceptive method for 1-3 years and another 46% for more than 3 years, indicating consistent acceptance of family planning. A sequential trend of nonuse, OC use, and finally sterilization was observed. OC use was highest among women in their late 20s with 2-3 children. Urban-rural residence and socioeconomic factors had little impact on OC use. An encouraging finding was that only 25% of respondents believed that the pill poses important health risks and 61% were aware that pregnancy and childbirth involve greater health risks than OC use. This finding is in opposition to the extremely high levels of misinformation about the dangers of OC use identified in other surveys in developing countries and probably reflects the fact that 77% of women in the present study reported receiving advice on contraception from family planning professionals.     

Contraceptive Use and Pregnancy Outcomes among Opioid Drug-Using Women: A Retrospective Cohort Study

Objective

The contraceptive needs of illicit opioid users differ from non-drug users but are poorly understood. The aim of this study was to describe contraceptive use and pregnancy outcomes in opioid-using women, and to examine their association with a range of risk factors.

Method

This retrospective cohort study used UK general practice records, Treatment Outcomes Profile and National Drug Treatment Monitoring System data, and a nested data validation exercise. A cohort of 376 women aged 20–61 years were in active treatment for opioid addiction in October 2010 at two specialised primary care practices in North-East England. Outcomes were age-adjusted prevalence estimates for contraceptive use and pregnancy outcomes in users of illicit opioids. The association between lifestyle-related risk factors and contraception was explored.

Results

Drug-using women made lower use of planned (non-condom) contraception (24% vs 50%, p<0.001), had more frequent pregnancy terminations (0.46 vs. 0.025, p = 0.004) and higher annual incidence of chlamydia (1.1% vs. 0.33%, p<0.001), when compared with age-matched population data. Specifically, there was low use of oral contraceptives (4% vs. 25%, p<0.001), IUCD (1% vs. 6%, p<0.001), and sterilisation (7% vs. 6%, p = 0.053), but higher rates of injectable contraceptives (6% vs. 3%, p = 0.003). A total of 64% of children aged <16 years born to this group did not live with their mother. No individual risk factor (such as sex-working) significantly explained the lower use or type of non-condom contraception.

Conclusions

This is the first study to describe planned contraceptive use among drug-users, as well as the association with a range of risk factors and pregnancy outcomes. The low uptake of planned contraception, set against high rates of terminations and sexually transmitted disease demonstrates the urgent clinical need to improve contraceptive services, informed by qualitative work to explore the values and beliefs influencing low contraceptive uptake.     

Epidemiology of endometriosis in women attending family planning clinics.

OBJECTIVE--To describe the epidemiology of endometriosis in women attending family planning clinics with special reference to contraceptive methods. DESIGN--Non-randomised cohort study with follow up of subjects for up to 23 years. Disease was measured by first hospital admission rates since endometriosis can be diagnosed with accuracy only at laparotomy or laparoscopy. SETTING--17 family planning centres in England and Scotland. SUBJECTS--17,032 married white women aged 25-39 years at entry during 1968-74 who were taking oral contraceptives or using an intrauterine device or diaphragm. About 99% of the women approached agreed to participate and annual loss to follow up was about 0.3%. MAIN OUTCOME MEASURES--Diagnosis of endometriosis, age, parity, and history of contraceptive use. RESULTS--Endometriosis was significantly related to age, peaking at ages 40-44 (chi 2 for heterogeneity = 30.9, p < 0.001). Endometriosis was not linked to duration of taking oral contraceptives. Nevertheless, the risk of endometriosis was low in women currently taking oral contraceptives (relative risk 0.4; 95% confidence interval 0.2 to 0.7), but higher in women who had formerly taken them (1.8; 1.0 to 3.1 in women who had stopped 25-48 months previously) compared with women who had never taken the pill. A similar pattern was seen for use of intrauterine devices (relative risk 0.4 (0.2 to 0.7) in current users and 1.4 (0.4 to 3.2) in users 49-72 months previously compared with never users). No association was found between endometriosis and use of the diaphragm. CONCLUSIONS--Oral contraceptives seem to temporarily suppress endometriosis. Endometriosis may be diagnosed late in women using intrauterine devices as pain and bleeding occur with both.     

Ineffective contraceptive use and its causes in a natural fertility population in southern Jordan

Based on our interview survey of 574 randomly selected married women from a rural population in the South Ghor district, Jordan, where traditional Arab customs have been persistently maintained, in this paper we analyze the age-specific marital fertility rates (ASMFRs) and contraceptive practices, especially the prevalence and duration of contraceptive use. The ASMFRs fitted the natural fertility pattern proposed by Coale and Trussell's model, and the total fertility rate was estimated to be 7.2. Even though the prevalence rate of modern contraceptive methods has reached 14.3%, because of the recent increase among young women in particular, the users had larger numbers of children than the nonusers and the duration of contraceptive use was short, especially at young ages (e.g., about 90% 24-month discontinuation probabilities in 15-19- and 20-24-year-olds). These ineffective contraceptive uses were related to traditional Arab norms, represented by the pooled proportion of "as many as possible" and "up to God" answers to the ideal number of children (70% of men and 30% of women).     

Effects of menstrual cycle and oral contraceptive use on calf venous compliance

Numerous studies have shown that the female sex hormones estrogen and progesterone have multiple effects on the vasculature. Thus our goal was to investigate the effects of estrogen and progesterone on calf venous compliance by looking for cyclic changes during the early follicular, ovulatory, and midluteal phases of the menstrual cycle and during high and low hormone phases of oral contraceptive use. Additionally, we wanted to compare the venous compliance of normally menstruating women, oral contraceptive users, and men. We studied eight normally menstruating women (23 +/- 1 yr of age) during the early follicular, ovulatory, and midluteal phases of the menstrual cycle. Nine triphasic oral contraceptive users (21 +/- 1 yr of age) were studied during weeks of high and low hormone concentrations. Eight men (23 +/- 1 yr of age) were studied twice within 2-4 wk. With the use of venous occlusion plethysmography with mercury in-Silastic strain gauges, lower limb venous compliance was measured by inflating a venous collection cuff that was placed on the thigh to 60 mmHg for 8 min and then reducing the pressure to 0 mmHg at a rate of 1 mmHg/s. Venous compliance was calculated as the derivative of the pressure-volume curves. There were no differences between early follicular, ovulatory, and midluteal phases of the menstrual cycle or between high and low hormone phases of oral contraceptive use (P > 0.05). Male venous compliance was significantly greater than in normally menstruating women (P < 0.001) and oral contraceptive users (P < 0.002). These data support a sex difference but also suggest that venous compliance does not change with menstrual cycle phase or during the course of oral contraceptive use.     

Reproductive mortality.

The transfer from traditional to modern methods of contraception in recent decades has been accompanied by a transfer of deaths from complications of pregnancy to deaths from complications of the modern contraceptive methods. In 1975, for example, it is estimated that there were more deaths at ages 25-44 years in England and Wales from adverse effects of oral contraceptive use than from all complications of pregnancy, delivery, and the puerperium combined. Thus maternal mortality is no longer an adequate indicator of the deaths associated with reproduction in the community. An alternative measure, the reproductive mortality rate should be used, which includes deaths from complications of contraceptive use as well as those from complications of pregnancy or abortion. The reproductive mortality rate in England and Wales seems to have declined continuously since 1950 for women aged 25-34. But after 1960 it increased for women aged 35-44, because of the higher mortality associated with oral contraceptive use in this age group.     

Use of the oral contraceptive pill by Austrian adolescents with emphasis on the age of onset,side effects,compliance and lifestyle

The present study investigated the use of the oral contraceptive pill in 880 Austrian high school girls. All participants filled in a questionnaire on lifestyle and menarche. Furthermore, subjects on the pill were asked about their preparation, age at first use, reasons why they take it, side effects and oral contraceptive compliance. All 139 subjects on the pill used low dose monophasic preparations. The girls started the pill at a mean age of 16.0 +/- 0.9 years for contraceptive and therapeutic reasons. The most commonly noted side effects were weight gain, an increase in breast size, fatigue and depression. The results also indicate that most users comply sufficiently. Regarding lifestyle, it can be stated that there is a correlation between the use of the pill and smoking, the frequency of consuming alcoholic drinks and being physically active.     

Fertility and family planning in Accra

A sample of 1000 currently married women aged 25-39 and living in 3 geographic areas of the Ghanaian capital were interviewed about their contraceptive knowledge and practice. Slightly over 90% of the respondents said that they had heard of ways to delay or prevent pregnancy. There was no difference between the 3 areas, but more of those aged 30-34 had heard about contraception. The chances that a respondent had heard about contraception increased with the level of education. Catholics were less likely to have heard of any contraceptive methods than Protestants. Also, women engaged in traditional informal occupations were the least likely to have heard of any contraceptive methods. Overall, education emerged as the most important differentiating factor. The pill, condom, and IUD were the best known methods. Regarding actual contraceptive practice, only 41% of the respondents were currently using some form of contraception, with about 19% using modern and 27% traditional methods. Results of contraceptive usage by user characteristics show that the majority of women in 2/3 of the areas rely on a mixture of traditional and modern methods; that the % of users (any method) increases with age up to 30-34 years, after which it decreases. The % of ever-users of any type of contraception in this study is highest for the highest education levels, at 84% for women with 2ndary and post 2ndary education. With the exception of the IUD, douche and folklore methods, better educated women have higher ever-use %s for both traditional and modern methods. While the %s of users increases with education for foam, diaphragm and withdrawal; the reverse is observed for the pill and IUD, probably due to fear of negative side effects. Overall, there are no significant variations in contraceptive use by migration status; but the % of non-users is highest among recent migrants who are also the least likely to have ever used modern methods. Fertility differentials across ethnic groups have been observed in Ghana. The Akan have the highest fertility, followed by the Ewe and Ga-Adangbe with moderate fertility, and the northern ethnic groups with the lowest fertility. The Akan also have the highest % of ever users of modern contraceptives, an inconsistency which may be explained by their recent recognition of the burdens of high fertility and their attempts to control it. Religious differences are pronounced, especially between the traditional category on the 1 hand, and Christians and Muslims on the other. Results of an analysis of variance suggests that family size is the strongest motivation for adopting modern contraception, and that it may be used for limiting rather than spacing births.     

Mortality among oral contraceptive users: 20 year follow up of women in a cohort study.

OBJECTIVE--To see whether the use of oral contraceptives influences mortality. DESIGN--Non-randomised cohort study of 17,032 women followed up on an annual basis for an average of nearly 16 years. SETTING--17 Family planning clinics in England and Scotland. SUBJECTS--Women recruited during 1968-74. At the time of recruitment each woman was aged 25-39, married, a white British subject, willing to participate, and either a current user of oral contraceptives or a current user of a diaphragm or intrauterine device (without previous exposure to the pill). MAIN OUTCOME MEASURES--Overall mortality and cause specific mortality. RESULTS--238 Deaths occurred during the follow up period. The main analyses concerned women entering the study while using either oral contraceptives or a diaphragm or intrauterine device. The overall relative risk of death in the oral contraceptive users was 0.9 (95% confidence interval 0.7 to 1.2). Though the numbers of deaths were small in most individual disease categories, the trends observed were generally consistent with findings in other reports. Thus the relative risk of death in the oral contraceptive users was 4.9 (95% confidence interval 0.7 to 230) for cancer of the cervix, 3.3 (95% confidence interval 0.9 to 17.9) for ischaemic heart disease, and 0.4 (95% confidence interval 0.1 to 1.2) for ovarian cancer. There was a linear trend in the death rates from cervical cancer and ovarian cancer (in opposite directions) with total duration of oral contraceptive use. Death rates from breast cancer (relative risk 0.9; 95% confidence interval 0.5 to 1.4) and suicide and probable suicide (relative risk 1.1; 95% confidence interval 0.3 to 3.6) were much the same in the two contraceptive groups. In 1981 the relative risk of death in oral contraceptive users from circulatory diseases as a group was reported to be 4.2 (95% confidence interval 2.3 to 7.7) in the Royal College of General Practitioners oral contraception study. The corresponding relative risk in this study was only 1.5 (95% confidence interval 0.7 to 3.0). CONCLUSIONS--These findings contain no significant evidence of any overall effect of oral contraceptive use on mortality. None the less, only small numbers of deaths occurred during the study period and a significant adverse (or beneficial) overall effect might emerge in the future. Interestingly, the mortality from circulatory disease associated with oral contraceptive use was substantially less than that found in the Royal College of General Practitioners study.     

Decreased spontaneous eye blink rates in chronic cannabis users: evidence for striatal cannabinoid-dopamine interactions

Chronic cannabis use has been shown to block long-term depression of GABA-glutamate synapses in the striatum, which is likely to reduce the extent to which endogenous cannabinoids modulate GABA- and glutamate-related neuronal activity. The current study aimed at investigating the effect of this process on striatal dopamine levels by studying the spontaneous eye blink rate (EBR), a clinical marker of dopamine level in the striatum. 25 adult regular cannabis users and 25 non-user controls matched for age, gender, race, and IQ were compared. Results show a significant reduction in EBR in chronic users as compared to non-users, suggesting an indirect detrimental effect of chronic cannabis use on striatal dopaminergic functioning. Additionally, EBR correlated negatively with years of cannabis exposure, monthly peak cannabis consumption, and lifetime cannabis consumption, pointing to a relationship between the degree of impairment of striatal dopaminergic transmission and cannabis consumption history.     

Assessing the reproductive behavior of on- and off-reservation American Indian females: characteristics of two groups in Montana

Only limited fertility and general reproductive health data exist on American Indians. Using data from the 1987 Montana American Indian Health Risk Assessment, we found that the fertility of American Indians in Great Falls and on the Blackfeet Reservation was similar to blacks in the U.S. and relatively high when compared with fertility of whites in the United States. The influence of the direct determinants of fertility (nuptiality, contraceptive use, and lactation) was very different for the populations examined in this study. Great Falls American Indians and the U.S. black population were similar regarding age at first sexual intercourse (very young), breastfeeding (low prevalence and short duration), planning status of pregnancies (high unplanned), and contraceptive use (only moderate use). In contrast, Blackfeet women on the reservation and the U.S. white population married relatively late, had very high contraceptive use, used effective methods of contraception, and had moderately high levels of breastfeeding. However, Blackfeet fertility was much higher than that of whites. Three interrelated reasons are suggested as possible explanations. Blackfeet couples either wanted high fertility, were relatively poor users of family planning methods, or used less effective methods until they had exceeded their desired family size after which time they turned to sterilization. These finds raise numerous questions concerning the social and economic factors that may account for these group similarities and differences. Further studies with much larger data sets are needed to address these issues adequately.     

Side effects and discontinuation of oral contraceptive use in southern Brazil

Oral contraceptives have many advantages, but sometimes also have side effects which can cause users to switch appropriately or inappropriately to less effective methods or abandon contraception. In Brazil, 2/3 of married women of childbearing age were using contraception in 1981, and 1/2 of these were using orals. Contraceptive behavior following reported side effects in users of oral contraceptives in Southern Brazil is examined in this study, in relation to diverse factors. Among 2904 currently-married women, aged 15-44, almost 75% reported that they had used the pill at some time, and of these, 45.6% were still doing so. Data on perceived side effects were gathered for all women. There was no independent medical evaluation of the effects, so the data did not necessarily represent actual prevalence of pill related problems. Women who reported problems with the pill were less likely to be current users (25%) than women who did not (65%). However, overall contraceptive prevalence was about the same in both groups (66.2% and 67.0% respectively), indicating that women who stop using oral contraceptives usually switch to another method. However, they are more likely to be using traditional methods than women in the general population, especially if they want more children. Termination of pill use varies little according to the type of problem reported. Women with problems who sought medical attention were more likely to stop using the pill, and 82.4% of women advised to stop by their physician did so, but the major factor affecting discontinuation was the reported experience of a problem. The most frequently reported problems were headaches (38.1%), nausea (34.1%), nervousness (27.9%), and vertigo (18.3%). Physician intervention should help to avoid women's abandoning oral contraceptives unnecessarily.     

Analysing the relationship between family planning workers' contact and contraceptive switching in rural Bangladesh using multilevel modelling

With a population of over 131 million and a fertility rate of 29.9 per 1000, population growth constitutes a primary threat to continued economic growth and development in Bangladesh. One strategy that has been used to cease further increases in fertility in Bangladesh involves using family planning outreach workers who travel throughout rural and urban areas educating women regarding contraceptive alternatives. This study uses a longitudinal database to assess the impact of family planning outreach workers' contact upon contraceptive switching and upon the risk of an unintended pregnancy. Using longitudinal data on contraceptive use from the Operations Research Project (ORP) of the International Centre for Diarrhoeal Disease Research (ICDDR,B) in Bangladesh, multiple decrement life table analysis and multilevel, discrete-time competing risk hazards models were used to estimate the cumulative probabilities of switching to an alternative form of contraceptive use after a woman engaged in a discussion with an outreach worker. After controlling for the effects of socio-demographic and economic characteristics, the analysis revealed that family planning outreach workers' contact with women significantly decreases the risk of transitioning to the non-use of contraceptives. This contact also reduces the risk of an unintended pregnancy. Family planning workers' contact with women is associated with the increased risk of a woman switching from one modern method to another modern method. The study results indicate that side-effects and other method-related reasons are the two primary reasons for contraceptive discontinuation in rural Bangladesh.     

Contraceptive experience and attitudes to motherhood of teenage mothers

Sexual experience is increasingly common among teenagers. Evidence suggests that while many teenage pregnancies are unintended, teenagers remain less than totally effective users of contraception. This study examines a sample of 102 teenage mothers (under age 20 at delivery) presented at antenatal booking clinics in Bristol Health District England. Of these, 25% were married at time of conception; 31 of them had been pregnant previously; 2/3 had used contraception previously. Contraceptive users were older than nonusers, more likely to be married, and more likely to be white. Most of the older users had been using the pill, and gave varied accounts of why they stopped. Just over 25% of the pregnancies were considered "planned" and about 1/2 the teenagers were upset on hearing the news of the pregnancy. 9 of the study pregnancies failed due to miscarriage (3), stillbirth (4), and neonatal death (2). Most of the girls who lost their babies came from parts of Bristol where infant mortality is high. 28.4% of the sample had previously used contraception but became pregnant without desiring to and were upset at the news. Many had given up a reliable technique (such as the pill) without substituting any alternative. This group presents a challenge for those providing contraceptive services, especially in view of the restricted opportunities available to working class girls.     

Contraceptive knowledge and attitudes in urban Ilorin, Nigeria

In Nigeria as in other African countries, population growth negatively affects economic development, and high parity affects maternal health. Breastfeeding, a common practice traditionally, is declining in some situations. This study was carried out in Ilorin, Nigeria. A sample population of 932 households stratified to represent different socioeconomic groups was used. 913 currently married women aged 15-35, who were in their prime childbearing ages, were interviewed on their contraceptive knowledge and on their attitudes towards modern contraception. In a bivariate statistical analysis, of 8 variables examined (i.e. ownership of a television, radio, religion, and other) only the woman's education, age, and area of residence within the city have significant independent effects on contraceptive knowledge. A linear logistic regression technic was also applied. 90% of the women interviewed thought that women should be free to practise family planning. Also, 95% of all the women believed that too frequent births could endanger the health of the mother and her children. Only the women with previous contraceptive knowledge overwhelmingly (80%) thought that the best way to prevent too frequent births is by family planning. 66.5% of those without previous contraceptive knowledge before this study suggested that traditional abstinence should be used and only 28.9% suggested family planning. Adequate awareness of the availability and usefulness of family planning methods can influence attitudes of women towards contraception and may also enhance contraceptive use. Better use can be made of broadcasting media, and efforts should be made to target younger, more fecund women, since there was evidence that more knowledge of family planning existed among women 30+ years old.     

The levonorgestrel intrauterine system in contraception

The levonorgestrel intrauterine system (LNG IUS) releases 20 microg/24 h of levonorgestrel from a polymer cylinder mounted on a T-shaped frame and covered with a release rate-controlling membrane. It is approved for 5-year use. The most outstanding features of LNG IUS are its high contraceptive efficacy and reduction of menstrual blood flow. No single mode of action can account for its contraceptive efficacy. The endometrium becomes thin and inactive, and the cervical mucus turns scanty and viscous. Although ovulation may be disturbed to some degree, estradiol production continues normally. The Pearl index for LNG IUS from large clinical trials is 0.1. Extrauterine pregnancies occur in 1 in 5000 users per year. Both the volume of menstrual blood loss and the number of bleeding days are reduced. During the first year of use, 20% of women become amenorrheic. There is an initial increase in the mean number of bleeding and spotting days, but in 3 to 6 months the number of bleeding and spotting days is the same as observed in copper IUD-users. The variation between individuals is wide and unpredictable. There are also additional health benefits secondary to the inactivation of the endometrium: increased hemoglobin, decreased dysmenorrhea, a possible decrease in pelvic inflammatory disease. LNG IUS may also decrease the growth of fibroids. LNG IUS is well accepted by users, with typical annual continuation rates above 80% in clinical studies.     

The Role of Quality Health Services and Discussion about Birth Spacing in Postpartum Contraceptive Use in Sindh,Pakistan: A Multilevel Analysis

IntroductionRapid population growth, stagnant contraceptive prevalence, and high unmet need for family planning present significant challenges for meeting Pakistan’s national and international development goals. Although health behaviors are shaped by multiple social and environmental factors, research on contraceptive uptake in Pakistan has focused on individual and household determinants, and little attention has been given to community characteristics that may affect access to services and reproductive behavior.MethodsIndividual and community determinants of contraceptive use were identified using multivariable multilevel logistic regression to analyze data from a 2014 cross-sectional survey of 6,200 mothers in 503 communities in Sindh, Pakistan.ResultsOnly 27% of women who had given birth in the two years before the study reported using contraceptives. After adjusting for individual and community characteristics, there was no difference in the odds of contraceptive use between urban and rural women. Women who had delivered at a health facility had 1.4 times higher odds of contraceptive use than women who delivered at home. Those who received information about birth spacing from a doctor or relatives/friends had 1.81 and 1.38 times higher odds of contraceptive use, respectively, than those who did not. Living in a community where a higher proportion of women received quality antenatal care and where discussion of birth spacing was more common was significantly associated with contraceptive use. Community-wide poverty lowered contraceptive use.ConclusionsQuality of care at the community level has strong effects on contraceptive use, independent of the characteristics of individual households or women. These findings suggest that powerful gains in contraceptive use may be realized by improving the quality of antenatal care in Pakistan. Community health workers should focus on generating discussion of birth spacing in the community. Outreach efforts should target communities where the demand for contraception appears to be depressed due to high levels of poverty.     

Depot medroxyprogesterone (Depo-Provera) and risk of breast cancer.

OBJECTIVE--To determine whether use of the injectable contraceptive depot medroxyprogesterone acetate (Depo-Provera) affects the risk of breast cancer in women. DESIGN--A population based case-control study. SETTING--Nationwide community study. SUBJECTS--891 Women aged 25-54 with newly diagnosed breast cancer were compared with 1864 women selected at random from the electoral rolls. INTERVENTION--Women were interviewed by telephone about past use of contraceptives and about possible risk factors for breast cancer. MAIN OUTCOME MEASURE--Relative risk of breast cancer in women who had used medroxyprogesterone. RESULTS--Medroxyprogesterone had been used by 110 patients and 252 controls. Overall, the relative risk of breast cancer associated with any duration of use was 1.0 (95% confidence interval 0.80 to 1.3). In women aged 25-34 the relative risk was 2.0 (1.0 to 3.8). The relative risk was highest in women aged 25-34 who had used the drug for six years or longer, although there were few women in this category. Women who had used it for two years or longer before age 25 had an increased risk of breast cancer (relative risk 4.6; 1.4 to 15.1). CONCLUSION--Despite the lack of an overall association these findings suggest that medroxyprogesterone may increase the risk of breast cancer in young women.     

Projected population persistence of eastern hellbenders (Cryptobranchus alleganiensis alleganiensis) using a stage-structured life-history model and population viability analysis

The population of eastern hellbenders (Cryptobranchus alleganiensis alleganiensis) in the Blue River, Indiana has undergone a dramatic decline over the last decade. Recruitment in these declining populations has been negligible, and populations are now composed almost entirely of older age classes (upwards of 20 years old). Given this dramatic decline, it is imperative to assess the impacts of these demographic patterns on population growth and long-term stability. Therefore, we developed a stage-structured, life-history model to examine the effects of varying levels of egg, juvenile, and adult survivorship on abundance, recruitment, and long-term population projections. We performed a sensitivity analysis of the model and determine which life-history parameters have the greatest potential to increase/stabilise hellbender population growth. Finally, we conducted a population viability analysis to determine the probability of extinction associated with varying management strategies. For eastern hellbender populations in Indiana, adults (especially females) are the most important component of long-term population viability. Sensitivity and elasticity analyses of the Lefkovitch matrix revealed that survival of adult and egg/larvae life-history stages are the most important for focused management efforts. Indeed, adults had the highest elasticity and reproductive value in the matrix model. Increasing survival by as little as 20% corresponded to the turning point at which the population ceased to decline and increased abundance (28% survival of egg/larvae). The importance of the transition from subadult to adult (transitional matrix element) was identified as an additional factor in maintaining abundance based on the relatively long period spent in this life-history stage (seven years for females). A population viability analysis was conducted to assess the likelihood and projected time frame of extinction for this population under no management (～25 years to complete extirpation; probability of extinction = 1) and if management efforts such as captive rearing and headstarting are undertaken (probability of extinction <0.2 at 25–30% survival of egg/larvae). Adult females had the greatest effect in reducing growth rate and population abundance when removed in exploitation simulations (91.3% versus 51.8% reduction in population growth rate), indicating translocation efforts should be designed to maintain females in the breeding pool. These models indicated that conservation management strategies aimed at ensuring the presence of adult females while concomitantly ameliorating survival at early life stages (population augmentation, translocations, introduction of artificial nest structures) are needed to stabilise the Indiana population of eastern hellbenders. This stage-structured model is the first to model eastern hellbenders and has broad implications for use across the geographic range where populations of eastern hellbenders are monitored and vital rates can be estimated.