ANU National Centre for Epidemiology and Population Health (NCEPH)

Permanent URI for this collectionhttps://hdl.handle.net/1885/138166

Since 1988, NCEPH has devoted itself to improving the population's health through discovery, training and the translation of research into effective health policy. We strive to provide a work environment that is supportive and enriched by expertise in the broad range of disciplines needed to achieve excellence in population health research.

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Open Access
Disease and the destruction of indigenous populations
(Canberra : National Centre for Epidemiology and Population Health, Australian National University, 1990) Kunitz, Stephen J.; National Centre for Epidemiology and Population Health (Australia)
My focus in this chapter is upon the impact that European contact has had upon non-Europeans. The topic is vast since indigenous populations, by which I mean the native peoples of non-European lands, are enormously diverse - a diversity that is matched by their disease experience. I shall proceed by examining the sources of diversity, on a series of progressively finer levels of analysis.
Open Access
Do treatment costs vary by stage of detection of breast cancer?
(Canberra : Australian National University, 1990) Butler, J. R. G. (James Robert Gerard), 1952-; Furnival C. M.; Hart, R. F. G.; Cawdell, G.; Brunello, M.; National Centre for Epidemiology and Population Health (Australia)
This paper reports the results of a study wherein full treatment data were collected from the medical records of 301 women treated for breast cancer at a major public hospital. The objective of the study was to ascertain whether, and to what extent, treatment costs for breast cancer vary by stage of detection of the disease. This issue is of importance in the economic evaluation of breast cancer screening programs, as any treatment cost savings arising from early detection of the disease should be offset against the costs of the screening program. The results indicate that there is a statistically significant relationship between stage of detection and treatment costs for breast cancer, with mean treatment costs being higher the more advanced is the disease on presentation. This relationship was found to be robust even aftertaking into account the age of patients, their discharge status (alive or deceased at last separation) and their year of first admission. The results also indicate that there is a substantial amount of variation in treatment costs within each stage of detection. Nevertheless, the between-stage variation in treatment costs is substantial and highly statistically significant, lending support to the contention that detecting this disease at an earlier stage may indeed significantly reduce treatment costs.
Open Access
The PFAS Health Study Phase II Research Protocols
(National Centre for Epidemiology and Population Health, The Australian National University, 2018-08-02) Kirk, Martyn; Korda, Rosemary; Clements, Archie; Lucas, Robyn; D’Este, Cate; Armstrong, Bruce; Mueller, Jochen; Jones, Alison; Miller, Adrian; Banwell, Cathy; Batterham, Philip; lal, aparna; Braunig, Jennifer; Housen, Tambri
Open Access
The PFAS Health Study: Data Linkage Study Research Protocol
(National Centre for Epidemiology and Population Health, The Australian National University, 2019-07-10) Korda, Rosemary; Law, Hsei Di; Armstrong, Bruce; D'Este, Catherine; Smurthwaite, Kayla; Trevenar, Susan; Lucas, Robyn; Miller, Adrian; Kirk, Martyn
Open Access
The PFAS Health Study Cross-sectional Survey and Blood Serum Study Research Protocol
(National Centre for Epidemiology and Population Health, The Australian National University) Kirk, Martyn; Todd, Katherine Margaret; Armstrong, Bruce; D'Este, Catherine; Trevenar, Susan; Smurthwaite, Kayla; Walker, Liz; Lucas, Robyn; Mueller, Jochen; Bräunig, Jennifer; Batterham, Philip; Miller, Adrian; Clements, Archie; Korda, Rosemary
Open Access
PFAS Health Study Component four: Data linkage study of health outcomes associated with living in PFAS exposure areas December 2021
(National Centre for Epidemiology and Population Health, The Australian National University, 2021) Law, Hsei Di; Armstrong, Bruce; D'Este, Catherine; Randall, Deborah; Hosking, Rose; Lazarevic, Nina; Trevenar, Susan; Smurthwaite, Kayla; Lal, Aparna; Lucas, Robyn; Mueller, Jochen; Clements, Archie; Kirk, Martyn; Korda, Rosemary
Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that may have adverse effects on the environment and human health. The primary aim of the PFAS Data Linkage Study was to examine whether adverse health outcomes were more common in people who had lived in towns with known PFAS contamination—Katherine in Northern Territory (NT), Oakey in Queensland (Qld) and Williamtown in New South Wales (NSW) (the ‘exposure towns’). To do this, we compared rates of selected health outcomes in these towns, to rates in other separate but similar areas in Australia not known to have PFAS contamination (the ‘comparison areas’). We conducted three separate studies that investigated four groups of health outcomes. Study 1 investigated maternal and infant (perinatal) health (15 outcomes); Study 2 examined childhood development (6); and Study 3 investigated cancer (23) and deaths due to specific causes (4)—a total of 48 outcomes. All studies used multiple data sources with records collected over many years, which were linked to create richer datasets for analyses. All data used were originally collected for administrative purposes. We only used data that did not identify individual people and no direct contact was made with anyone whose data were included in the studies. Over the three separate studies, for most of the health outcomes studied we did not conclude that rates were higher in the towns than the comparison areas. For several health outcomes studied, we observed higher rates in one but not the other two towns. These were: in Katherine, prostate cancer; in Oakey, stillbirth, developmental vulnerability in two domains (physical health and wellbeing, and communication skills and general knowledge) and laryngeal cancer; and in Williamtown, postpartum haemorrhage (heavy blood loss following pregnancy), pregnancy-induced hypertension (high blood pressure), kidney cancer and lung cancer. Rates of death from coronary heart disease were higher in both Oakey and Williamtown. For most of these health outcomes, we estimated the differences between the towns and comparison areas to be relatively small. For others, the differences were of modest size, but our estimates were imprecise, meaning the likely size of each difference could be anywhere between quite small to quite large. Even though our studies included almost everyone who had ever lived in the towns in the years we had available data (in some cases dating back to 1983), some of the conditions studied are uncommon and we observed only a few cases. For these outcomes, we could not precisely estimate the differences between the towns and comparison areas, and there is very little we can say about whether a difference really exists. Due to the nature of our studies, there were certain design limitations. We were unable to fully account for certain risk factors (e.g. smoking) that could have led to observed differences in rates (or lack of them) between the towns and comparison areas (‘confounding’). In particular, we were not able to account for socioeconomic factors as well as we would have liked. This is important, as socioeconomic conditions are strongly linked to health. In addition, some findings could have arisen just by chance alone and not because an association truly exists. In light of the above, while there were higher rates of some adverse outcomes in individual towns, the evidence suggesting that this was due to living in these areas was limited. We did not have direct measurements of PFAS exposure and we cannot rule out that the higher rates were due to chance or confounding. Further, there was low consistency in our observations across the three towns (something we would not expect if PFAS caused an outcome), and there is limited evidence from other studies observing similar results or explaining how potential biological processes can result in PFAS causing these effects in humans. Overall, our findings are consistent with previous studies, which have not conclusively identified causative links between PFAS and these health outcomes.
Open Access
PFAS Health Study Component three: Cross-sectional survey of self-reported physical and mental health outcomes and associations with blood serum PFAS December 2021
(National Centre for Epidemiology and Population Health, The Australian National University, 2021) Lazarevic, Nina; Smurthwaite, Kayla; Trevenar, Susan; D'Este, Catherine; Batterham, Philip; Lane, Jo; Armstrong, Bruce; Lucas, Robyn; Clements, Archie; Banwell, Cathy; Hosking, Rose; Joshy, Amelia; Gad, Imogen; Law, Hsei Di; Mueller, Jochen; Bräunig, Jennifer; Nilsson, Sandra; Lal, Aparna; Randall, Deborah; Miller, Adrian; Korda, Rosemary; Kirk, Martyn
Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that may be harmful to the environment and human health. The aim of the PFAS Health Study Cross-sectional Survey was to examine health conditions and concerns among people who had lived or worked in Australian communities with known PFAS contamination. This included Katherine in the Northern Territory, Oakey in Queensland, and Williamtown in New South Wales (the ‘exposed communities’). We surveyed people in these communities who provided a blood sample for PFAS testing in the Australian Government-funded Voluntary Blood Testing Program. We also surveyed people in similar communities in Australia not known to have PFAS contamination. This included Alice Springs in the Northern Territory, Dalby in Queensland, and Kiama and Shellharbour in New South Wales (the ‘comparison communities’). We did this through Services Australia, who sent invitations to a random sample of people on the Medicare Enrolment File in the comparison communities, on behalf of the PFAS Health Study team. We asked people in exposed and comparison communities to complete an online or paper survey that asked about their demographic details; where they had lived and worked; whether they had ever been diagnosed with any of 32 health conditions; and the state of their mental health. We also asked people in exposed communities about their health concerns and use of healthcare related to the PFAS contamination. We measured levels of PFAS in blood to see how health conditions varied with different levels of PFAS. We focused on three PFAS that were found in the blood of most participants in the exposed communities: perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonic acid (PFHxS). In total, 917 people from the exposed communities and 801 from the comparison communities completed the survey. We compared the percentage of people with different health conditions in the exposed and comparison communities. People in Katherine were more likely to report cancer (especially breast cancer) and liver disease (especially fatty liver disease) than people in Alice Springs. In Williamtown, people were more likely to report rheumatoid arthritis, hypercholesterolaemia (high cholesterol), type II diabetes, and problems with fertility compared to people in Kiama and Shellharbour. In Oakey and Dalby, the numbers of people surveyed were too small to make reliable comparisons. While we observed differences between exposed and comparison communities, the findings were not consistent across exposed and comparison community pairs. The reported health conditions could have occurred at any time, even before a person lived or worked in a community exposed to PFAS. In addition, health conditions were self-reported by survey participants and may not have been diagnosed by a health professional. We found that people with higher PFAS levels were not more likely to report most diseases. However, the results varied across the different communities and PFAS. For example, for a doubling of the blood level of PFOS, people in Katherine were 29% less likely to report breast cancer, whereas in Williamtown people were 15% more likely to report breast cancer. For one chemical, PFOA, which was not elevated in people in exposed communities compared to people in comparison communities in the PFAS Health Study Blood Serum Study, we found that a doubling of blood levels was associated with more people with high cholesterol, gout, and hypothyroidism in different exposed communities. People living in exposed communities reported much higher levels of mental distress and worry than people in comparison communities. People who worked with firefighting foams containing PFAS and people who used bore water on their properties reported higher levels of worry and concern than people who did not. In the exposed communities, one in three people reported being ‘very’ or ‘extremely’ concerned about their health and one in five people had serious concerns about their mental health. People surveyed in these communities also reported concerns about their finances, the stigma of living in exposed communities, and uncertainty about the future. The survey participants from the exposed communities were not randomly sampled, rather people chose to participate. The results may therefore represent the experiences of people who were more worried about PFAS or were more likely to believe an illness was related to PFAS because of their known exposure. The results may not represent the experience of all people living in the communities. In the comparison communities, we randomly sampled people, but a very small number of the invited people completed the survey (only 3%). In addition, some of the reported results could be due to chance. Because this is a cross-sectional survey, we cannot draw conclusions about whether PFAS could have caused health conditions. While survey participants reported higher percentages of some health conditions in individual communities, these findings were not consistent across communities, and were not clearly related to levels of PFAS in blood. In contrast, there was consistency when looking at mental health. We observed higher levels of distress and worry in people from exposed communities, particularly among those who may have been exposed to PFAS at work, than in people from comparison communities.
Open Access
PFAS Health Study Component two: Blood serum study of PFAS exposure, related risk factors and biochemical markers of health December 2021
(National Centre for Epidemiology and Population Health, The Australian National University, 2021) Smurthwaite, Kayla; Lazarevic, Nina; Bräunig, Jennifer; Mueller, Jochen; Nilsson, Sandra; D'Este, Catherine; Lucas, Robyn; Armstrong, Bruce; Lal, Aparna; Trevenar, Susan; Law, Hsei Di; Gad, Imogen; Hosking, Rose; Joshy, Amelia; Clements, Archie; Lane, Jo; Batterham, Philip; Banwell, Cathy; Miller, Adrian; Randall, Deborah; Korda, Rosemary; Kirk, Martyn
Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that may be harmful to human health. The main goal of the Blood Serum Study was to see whether people who lived or worked in Australian communities affected by PFAS contamination had higher levels of PFAS in their blood. The three communities were Katherine in the Northern Territory (NT), Oakey in Queensland (Qld) and Williamtown in New South Wales (NSW)—the ‘exposed communities’. To do this, we compared blood levels of PFAS in people from the exposed communities to blood levels of PFAS in people in who lived in similar communities without environmental PFAS contamination. The three communities without contamination were Alice Springs in the NT, Dalby in Qld, and Kiama and Shellharbour in NSW—the ‘comparison communities’. From 2016 to 2020, people from the exposed and comparison communities provided a blood sample for PFAS testing and completed a questionnaire. A medical laboratory measured the levels of nine types of PFAS in blood. Only perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS) and perfluorooctanoic acid (PFOA) were detected in more than 80% of all blood samples. Average (geometric mean) PFAS levels of participants from the exposed communities were higher than participants from the comparison communities. Although, PFOA levels were similar in the exposed and comparison communities. Across the three exposed communities, the average PFAS levels in blood ranged from 4.9 to 6.6 nanograms per millilitre (ng/mL) for PFOS, from 2.9 to 3.7 ng/mL for PFHxS and from 1.3 to 1.8 ng/mL for PFOA. Across the three comparison communities, the PFAS levels in blood ranged from 2.5 to 3.3 ng/mL for PFOS, from 0.7 to 1.2 ng/mL for PFHxS and from 1.2 to 1.4 ng/mL for PFOA. PFOS and PFHxS were the main ingredients of the firefighting foams that contaminated the environment of the exposed communities. About half of participants from the exposed communities had high blood levels of PFHxS. About a third had high blood levels of PFOS. We investigated what may have led to participants who lived in the exposed communities having high levels of PFAS in their blood. We identified several risk factors for a person having a high blood level of PFOS or PFHxS in their blood, including consuming bore water or certain locally grown foods, living in an exposed community for a long period of time and exposure to firefighting foams in the workplace. Most participants from the exposed communities reported that they changed how much they used bore water or ate locally grown foods once they knew about the PFAS contamination. A medical laboratory also measured different chemicals related to health (biochemical markers) in blood samples, such as cholesterol, so we could see how they vary with PFAS levels in blood. Overall, there were few instances where higher PFAS levels were associated with higher or lower levels of biochemical markers. One example was that participants from Williamtown who had higher PFOS, PFHxS or PFOA levels in their blood also had a higher level of cholesterol in their blood. Higher levels of cholesterol in blood may lead to blockages in the coronary arteries, the blood vessels that carry oxygen into the heart muscle. Another example was for blood tests related to kidney function. Participants from Katherine and Williamtown who had higher PFAS levels in their blood also had higher levels of uric acid in their blood. All of these differences in biochemical markers were small and unlikely to lead to poor health. Further, higher PFAS levels in blood may not be the causes of the differences in biochemical markers but the consequences of them. For example, someone with poor kidney function may not be able to excrete PFAS from their body as easily as someone with normal kidney function, which may result in higher PFAS levels in blood. Blood levels of PFAS in the exposed communities were similar to those in some communities in the United States of America affected by environmental PFAS contamination from firefighting foams, but lower than in a community in Sweden. Consuming bore water or certain locally grown foods were risk factors for high levels of PFAS in blood. Changes in behaviour could limit people’s intake of PFAS and blood levels for most people will decline naturally over time
Open Access
A model for estimating the incremental cost of breast cancer screening programs
(National Centre for Epidemiology and Population Health, Australian National University, 1991) Butler, J. R. G.; Hart, R. F. G
Open Access
Aboriginal fertility in Central Australia
(National Centre for Epidemiology and Population Health (NCEPH), Australian National University, 1989) Khalidi, Noor A.
Open Access
Aboriginal fertility: trends and prospects
(National Centre for Epidemiology and Population Health, Australian National University, 1989) Gray, Alan
Open Access
The PFAS Health Study Focus Groups Research Protocol
(National Centre for Epidemiology and Population Health, The Australian National University, 2017-11-30) Kirk, Martyn; Banwell, Cathy; Housen, Tambri; Smurthwaite, Kayla; Trevenar, Susan
This protocol sets out the methodology for the collection and analysis of data for the PFAS Health Study: Focus Groups Study.
Open Access
The PFAS Health Study Component One: Oakey, Williamtown and Katherine Focus Groups Study
(National Centre for Epidemiology and Population Health, The Australian National University, 2019-02) Banwell, Cathy; Housen, Tambri; Smurthwaite, Kayla; Trevenar, Susan; Walker, Liz; Todd, Katherine; Rosas, May; Kirk, Martyn
This report details the findings from a series of focus group discussions held in Oakey (Qld), Williamtown (NSW), and Katherine (NT) between January and August 2018. The main aim of this study was to understand participants’ views and experiences of PFAS (per- and polyfluoroalkyl substances) contamination in their local area, with a focus on participants’ health concerns. Residents in these communities have been potentially exposed to PFAS chemicals. Potential exposure pathways varied between communities but include the use of contaminated water, including bore and river water on their properties, as well as town water. Less important potential exposure sources were eating locally produced foods and bush foods, through work activities, and in some instances through direct contact with firefighting foams. Four focus group discussions were held in each community, with 46, 36 and 29 participants attending in each of Williamtown, Oakey and Katherine respectively. One focus group discussion in each of the three communities was dedicated to Defence staff, contractors and family members. In Oakey, there were slightly more men than women, Williamtown focus groups contained roughly the same number of men and women, and in Katherine, there were predominately more women who attended the focus groups. Overall, the non-Aboriginal community groups contained slightly more people over the age of 50, more people who owned their own properties, and more who had lived in the area for longer than ten years. In Katherine, an additional three focus groups of 69 participants were held in local Aboriginal communities. The Aboriginal focus groups were larger, included more women who were often accompanied by children, and were held on community land. Participants voiced concerns related to their health and PFAS exposure. Children were considered more vulnerable due to their young age and exposure from growing up in affected areas. Participants were particularly concerned about the onset of cancers and the deterioration of existing health conditions. Another major concern for many participants was the stress and anxiety related to the duration of the PFAS contamination and uncertainty with respect to the long-term impact on health, specifically for their children. In addition to the above concerns, Aboriginal participants were also worried about the health of their children, contamination of river foods and bush tucker, and the overall impacts on country. Many participants were concerned about continuation of uncertainty and feeling unable to sell their property, being “stuck” in their community and lacking options to “move on”. Participants in the group discussions asked for greater transparency and consistency in the information they received. They discussed options that they thought would reduce their anxiety and provide information or pathways that could lead them out of their current situation soon. The findings from the focus group discussions have been used to contribute to the questionnaire design for a cross-sectional survey on health effects of PFAS. This report details the experiences and emotions of people who have been affected by the PFAS contamination.
Open Access
The PFAS Health Study: Systematic Literature Review
(National Centre for Epidemiology and Population Health, The Australian National University, 2018-04) Kirk, Martyn; Smurthwaite, Kayla; Braunig, Jennifer; Trevenar, Susan; D'Este, Catherine; Lucas, Robyn; Lal, Aparna; Korda, Rosemary; Clements, Archie; Mueller, Jochen; Armstrong, Bruce
This review examined all published research into the human health effects of exposure to perfluoroalkyl and polyfluoroalkyl substances, commonly known collectively as PFAS. PFAS chemicals are very resistant to heat and to degradation in the environment, and they persist for quite long periods in the human body. They were extensively used in fire-fighting foams, which were commonly used in fire drills at airports, and in household products, such as protective coatings on furniture and non-stick surfaces on cookware. PFOS (perfluorooctane sulfonic acid) and PFOA (perfluorooctanoic acid) were the two most commonly used PFAS chemicals. We reviewed research published up until February 7th 2017. We found 221 separate scientific publications that reported new results of relevant research in humans. These publications covered effects on reproduction, on pregnant women and their newborn babies, on body metabolism, on major body systems, including brain and nerves, heart and blood vessels, airways and lungs and the immune system, on specific conditions such as overweight, diabetes and cancer, and on thyroid gland function. The people they studied included people who worked in plants manufacturing these chemicals, firefighters, people with higher than usual exposure because of contamination of water supplies and people in the general community, whose exposure was ascertained by measuring PFAS chemicals in their blood. We found sufficient evidence that higher levels of PFOS or PFOA in a person’s blood can lead to higher blood cholesterol levels. High blood cholesterol is associated with heart disease. PFOS and PFOA, however, appeared only to increase cholesterol levels by a small amount. We found limited evidence that higher levels of PFAS in the blood resulted in slightly higher levels of uric acid in the blood. Uric acid is a normal body product and is removed by the kidneys. In a small number of studies, however, we also found limited evidence that high PFAS levels in the blood reduced kidney function or were associated with chronic kidney disease. Since PFAS chemicals are excreted by the kidneys it is possible PFAS does not cause poor kidney function, rather that poor kidney function caused by something else causes increase in PFAS levels in blood. This possibility of “reverse causation” might also explain the association of higher uric acid levels with higher PFAS levels in blood. We found limited evidence in a small number of relevant studies that PFAS exposure caused kidney and testicular cancers and that higher levels of PFAS in the blood resulted in lower levels of antibodies than usual following vaccination against some vaccine preventable infections. We found inadequate evidence that PFAS caused other health effects.
Open Access
Summary report on use of e-cigarettes and relation to tobacco smoking uptake and cessation, relevant to the Australian context
(The Australian National University, 2020-09) Banks, Emily; Beckwith, Katie; Joshy, Grace
This document provides a summary of work conducted to date on a review of the health impacts of e-cigarettes, commissioned by the Australian Government Department of Health. This summary review includes content from the following reports: 1. Review of smoking prevalence and trends in Australia 2. Review of smoking prevalence and trends in the Aboriginal and Torres Strait Islander population 3. Review of evidence regarding changes in smoking behaviour with decreasing smoking prevalence, including that relating to the “hardening hypothesis” 4. Review of the patterns of e-cigarettes use 5. Systematic review of evidence regarding combustible smoking uptake in relation to e-cigarette use; and 6. Systematic review of evidence regarding the efficacy of e-cigarettes for combustible tobacco or nicotine cessation. The findings presented here should be regarded as preliminary; many are in the process of undergoing peer-review or will undergo peer-review in the future. The next stage of the program of work is to review health outcomes in relation to e-cigarette use and to conduct a public health assessment of e-cigarettes for Australia; these will be completed by end June 2021.
Open Access
The Bangladesh arsenic crisis: Myth or slowly developing tragedy?
(The Australian National University, 2001)
Open Access
Why do the children of the poor die in Dhaka, Bangladesh
(The Australian National University, 2001)
Open Access
Pavement-dwelling in Dhaka: A life-threatening environment?
(The Australian National University, 2001)
Open Access
Is there an urban health crisis? An investigation of the slums of Dhaka, Bangladesh
(The Australian National University, 2001)
During the last fifty years the rapidly growing cities of the developing world have been characterised by their relatively low mortality levels in comparison to rural areas - in contrast to the situation of nineteenth century European cities. Concerns, however, have risen that this advantage no longer holds especially among the poorer sections of the urban communities. This is a particular worry as the urban population is set to become the majority population in these countries in the next few years. This paper uses data from a new survey of poorer Dhaka, Bangladesh to explore some of the factors that influence health status and health behavior. Dhaka is one of the world's most rapidly growing cities, a growth driven in large part by the influx of the very poor and those most likely to suffer from ill health and to be disadvantaged in gaining access to heal th services.
Open Access
Men's perspectives on fertility and fatherhood in urban Kilimanjaro
(The Australian National University, 1997)
This paper discusses male perspectives on reproduction and parenthood, an important and under-researched aspect of population dynamics in sub-Saharan Africa. Findings from recent work in the city of Moshi, Kilimanjaro (Tanzania) suggest that a range of concerns about fertility and family life among men have yet to be documented and analysed. Men frequently expressed their concerns about fertility desires and family relations in terms of a gendered experience of social and economic hardship. In this paper, in-depth interviews and data from male and female surveys have been used to examine fertility desires of younger men, the timing of their entry into reproductive life, and cultural values connected with the role of fathers in shaping the character of children. Such an inquiry is especially relevant in Kilimanjaro, where desired family sizes are much lower, and contraceptive use is much higher than anywhere else in Tanzania. It is apparent that demographic trends and shifts in the nature of productive life in Kilimanjaro have necessitated changes in the character of parenthood and the meaning of children. Consequently, cultural values surrounding reproduction are undergoing substantial change. Men cannot be thought of as a broadly pronatalist bloc, or even as significantly more desirous of children than their spouses. Although men's actions towards their reproductive partners and their children are culturally directed, they are expressed in local discourse as being highly situational and motivated by the external influences of economic and social constraint.