Assessing the potential of condom use to prevent the spread of HIV: a microsimulation study.

In this study, a microsimulation model is used to assess the potential impact of condom use on women's lifetime risk of acquiring HIV in rural southern Malawi. The model draws on survey data for information on sexual activity, marriage and divorce, and on the biomedical literature for input parameters governing the transmission and spread of HIV and other sexually transmitted diseases (STDs). We show that lifetime risk could be as high as 42 percent with no condom use and as low as 8 percent if everyone consistently uses condoms with nonmarital partners.

Explaining trends in teenage childbearing in Sweden.

The teenage fertility rate fell precipitately in Sweden after 1966 and is now one of the lowest in Europe. This decline can be seen in the context of major reforms enacted in 1975 whereby the school sex-education curriculum was revised, contraceptive services were improved, and abortion was provided free and on demand. By means of microsimulation, the possible roles of contraception and induced abortion in causing teenage fertility to fall are examined.

Consequences of current patterns of Pap smear and colposcopy use.

OBJECTIVES - To describe age specific frequencies of Pap smear and colposcopy use in the Australian Capital Territory (ACT) and to estimate the cumulative effects of current patterns of use. SETTING - Frequencies of Pap smear and colposcopy use were estimated for the financial year from 1 July 1989 to 30 June 1990. Eligible women were between the ages of 15 and 74, living in the ACT.

Education and hysterectomy.

A small Canberra survey provided the opportunity to investigate the observation that tertiary education is associated with lower hysterectomy rates. Despite the sample's being small and unrepresentative of either the Australian or even the Canberra population, it was possible to replicate a simple version of a national model of hysterectomy. Tertiary education remained strongly predictive of a low rate of hysterectomy.

Social roles and physical health: the case of female disadvantage in poor countries.

Women's culturally and socially determined roles greatly impair their health and that of their children through a complex web of physiological and behavioural interrelationships and synergies that pervade every aspect of their lives. Women's roles also affect their use of health services since modern health care has been absorbed so successfully into traditional structures that families tend to allocate it, like food, according to characteristics such as sex and age. Change may be occurring through the agency of female education and a redefinition of familial relationships, both of which operate to improve women's position, and hence their health.

Health of populations in northern Queensland aboriginal communities: change and continuity.

We show that Australian Aborigines living in North Queensland have had an impressive decline in infant mortality over the past 50 years. Since the early 1970s, much of the decline can be attributed to preventive and curative medical services. On the other hand, the growth trajectory of infants and children has improved only slightly since the early 1970s, and mean and median weights are still well below international standards.

Correlates of hysterectomy in Australia.

With around one in five women undergoing hysterectomy by the age of 50, the prevalence of hysterectomy in Australia is greater than in Europe but less than in the United States. In this paper, data from a nationally representative sample survey of 2547 Australian women aged 20-59 years are employed to identify correlates of hysterectomy and tubal sterilization over the last 30 years. Physiological, socio-economic and supply-side factors all influence the propensity to undergo hysterectomy, and a comparison with the correlates of tubal sterilization reveals parallels and contrasts between the determinants of the two operations.

Premature discontinuation of contraception in Australia.

Life-history data from a nationally representative survey of Australian women were used to examine discontinuation of contraceptive methods because of accidental pregnancy, side effects or dissatisfaction. The pill was the most successfully used method, with a first-year discontinuation rate of 10% for all three reasons. Side effects dominated the reasons for the premature discontinuation of both the pill and the IUD, while the reasons for discontinuing the condom stemmed equally from pregnancy and dissatisfaction with the method.

Trends in contraception and sterilization in Australia.

Life-history data collected in a national survey of women in 1986 are used to derive the first national estimates of trends in contraception and sterilization in Australia over the last 30 years. The pill rapidly became the method of choice after its release in 1961. The intrauterine device, the other truly modern method, has never attained the same popularity.

The family histories of Australian women.

"This paper exploits retrospective life-history data to examine changing age-specific patterns of co-residence of Australian women between the ages of 20 and 59 years at interview in 1986. Overlaying histories of leaving home, marital unions and childbearing, we identify cohort changes in the time spent before leaving the parental home, in transition between leaving home and forming a conjugal union, in times spent in union and times spent with children. Our analyses show that, despite massive recent declines in fertility and nuptiality, and a greater diversity in living arrangements, the nuclear family of couple and children remains the most common household unit and is unlikely to lose its pre-eminence in the near future.

Do gravidity and age affect pregnancy outcome?

Fetal loss has generally been found to vary with gravidity, previous experience of fetal loss, and maternal age, but the literature is divided on the reasons for these associations. In this paper we examine pregnancy histories obtained retrospectively from a nationally representative one-in-one-thousand sample of women in Australia aged 20 to 59 years. The relations of fetal loss ratios with both gravidity and previous outcome are consistent with heterogeneity of risk over the study population and a stopping rule, whereby high-risk women undertake more pregnancies than low-risk women to achieve the same number of live births.

Mortality of wild and captive chimpanzees.

Mortality of chimpanzees in the wild (Gombe National Park) and in captivity (Taronga Zoo, Sydney and Melbourne Zoo) was compared using standard cohort life table techniques. Overall mortality probabilities up to age 30 were compared using a logrank test. No significant difference in overall mortality was revealed, and the mortality curves did appear to be surprisingly similar, but there were nevertheless some differences in the distribution of mortality.

Some methodological considerations in the analysis of current status data.

Recent attention has focused on the length of the post partum period of infecundity in those societies where child-spacing has traditionally been achieved through post partum sexual abstinence or prolonged breast-feeding. The tabulation of proportions of women abstaining at interview by the age of the youngest child has been suggested as a technique free of problems of digital preference and memory lapse, while being otherwise equivalent to the distribution of the proportion of women abstaining by completed months since their last confinement, calculated from retrospectively-collected durations of abstinence. Both stochastic and deterministic models demonstrate that the techniques are comparable only when they are applied to non-recurrent events such as first marriage.

Models of contemporary Dutch family building.

Summary Recent data suggest that the level of use of oral contraceptives in the Netherlands is perhaps the highest in the world. Moreover, the greatest recent change in family building patterns is the tendency of newly weds to postpone their first birth. A micro-simulation model was developed to test the effect on fertility of such a change.