The study of the distribution of matrimonial distances is extremely important in the understanding of human population structure. The existing models of matrimonial migration are reviewed here. An assessment of the roles played by various social, cultural, economic, religious and linguistic factors in shaping the distribution of matrimonial distances has been made, with special reference to India.

The Tokelau Island Migrant Study is outlined. It is a multi-disciplinary study of health and social change in the Tokelau islanders, following up emigrants to New Zealand (NZ). In this paper fertility and related aspects are examined, comparing pre-migrants (persons subsequently known to have emigrated to NZ) with non-migrants. Pre-migrant females tended to be younger, to marry later, to be less often childless and to have suffered more miscarriages, than non-migrants. Tokelau parity lagged behind other Polynesian populations due to later marriages, and reached a level below that of the more westernized Rarotongans and NZ Maoris.

Tokelau life expectancy was estimated to be 62·2–62·6 years for males and 62·9–66·4 years for females.

The success of a compulsory sterilization programme depends on obtaining a correct history of family size from the couples concerned. Accordingly, we carried out a feasibility study at Prabhadevi Municipal Hospital, Bombay. At registration for confinement the women were required to produce some documentary proof such as a ration card, Employee's State Insurance Scheme card, or a letter from the Sarpanch of Gram Panchayat for women coming from villages, to indicate the number of their living children. The difficulties met by the staff in obtaining the necessary information and the problems of the women in providing documentary evidence are discussed, together with the results of the survey.

This paper examines the antifertility effects of an IUD (Lippes Loop) subsequent to the discontinuation of its use. The experiences of 4449 urban Taiwanese women who discontinued the use of the Lippes Loop initially inserted during the period July 1962 to May 1965 are analysed. These women were followed annually for 6 to 9 years through clinic visits and home interviews. The effect of duration of IUD use on average fecundability and sterility is examined after controlling for women's age at discontinuation of use of the IUD. The results indicate that, among Taiwanese women, the level of sterility increases and the average fecundability decreases with the increase in the duration of IUD use. These differentials are quite substantial and are mainly observed among those women who were at least 30 years of age at the discontinuation of IUD use. Various implications of this finding are discussed. The results refer only to the Lippes Loop and cannot be generalized for other types of IUD.

Matrices are derived for converting the proportions of couples wanting various completed family sizes to proportions attaining given sizes of families at a given time, based on a simulation model in which couples commence the regular use of contraception as soon as the decision is made to have not more than one further child. The matrices are adapted to include a proportion of ‘prospective aborters’ who are prepared to have recourse to abortion if contraception fails. A measure of consistency between the family size preferences estimated for different durations of marriage is introduced. This measure, together with the conversion matrices, is used to estimate the distribution of aborters and of family size preferences among a cohort of women married in England and Wales in 1920–24 at ages 20–24.

The percentage of accidental pregnancies, the Pearl pregnancy rate and the life-table method have all been used to study the effectiveness of contraception in Belgium, using data from the Second National Fertility Survey (1971), which covered 3397 Belgian women in the age group 30–34 years. Though all three methods yield generally similar results, it is only by using the third method that we can obtain in an optimum way changes in contraceptive effectiveness by birth order and birth interval.

Generally, contraceptive effectiveness is low, the cumulative failure rate for the first 12 months of all intervals amounting to 18%. This holds even for intrinsically extremely reliable methods, such as the pill (4%). The efficiency of contraception, however, improves with increasing duration of marriage. This is attributable not only to a shift towards more effective methods, but also to a better application of less reliable methods, such as withdrawal. It remains questionable whether the increase in effectiveness, especially of a method such as withdrawal, is not partially based on induced abortion.

The findings also clearly reveal the dual aspect of the contraceptive behaviour in the sample: spacing until desired family size is achieved, and prevention thereafter.

The efficiency of contraception decreases with increasing family size, whatever birth interval is considered.

At a hospital contraceptive clinic with between 1200 and 2400 new clients each year, regular recording is made of the social and personal characteristics of the clinic users together with their contraceptive and reproductive histories. An analysis has been made of the differences found between those accepting the pill and those the intrauterine device (IUD) at their first attendance. Age and parity show marked differences and these are related to employment and ethnic origin. Previous contraceptive use showed distinct differences; IUD acceptors were more likely to have had induced abortions. These findings are discussed in relation to the prevalent use of these two methods and it is suggested that IUD fitting should be more widely available.

This paper reports a pilot study of thirteen children with epilepsy and their families; the parents' efforts to obtain help for the child and the effect of the child's disability on the family relationships are described. About half of the parents did not consult the family doctor immediately after the first appearance of signs of epilepsy (patient delay). About a quarter of the family doctors delayed referral of the patient with epilepsy to the specialist (doctor's delay). Another 3 years passed, on average, before the patient reached a special centre or clinic for epilepsy (specialist delay); in three-quarters of all cases the first step to get there was taken by the parents and not by the specialist and chance plays an important role in determining how the entry into this third echelon is achieved. Reasons for the search for more specialized help were: dissatisfaction with the results of the treatment and the kind of rapport with the second echelon specialist. The out-patient clinic for epilepsy is generally favourably commented on because the expert medical advice is combined with the availability of a social worker, thus offering support with social problems also. As regards the influence of the illness on the family, there is evidence that family life is disrupted to a greater or less extent. The parents experience psychological stress and are generally apprehensive lest something will happen to their child. In a number of cases the relationships between siblings are rather disturbed. The parents, especially mothers, tend to (over-)protect the child with epilepsy. The child with epilepsy has a relatively isolated position in his social environment; he has few informal or formal social contacts with his peer group. The condition epilepsy contributes to a diminution of expectations for the future and curtailment of scholastic behaviour.

New South Wales law on abortion was liberalized by judicial interpretation in 1971. This paper describes the characteristics of the first 1007 women attending a free-standing clinic for induced abortion after it opened in 1974. Compared with Census data for New South Wales females of child-bearing age, the sample contained an over-representation of women who were relatively younger at conception, never married, divorced or separated, born outside Australia, of Catholic religious background, and worked as nurses or in factories. In comparison with background information about abortion experience before 1971, the clinic sample appeared to feel less anxiety and distress during the abortion sequence.

During the century before its final evacuation in 1930 the population of St Kilda declined from over 100 to 36. While undoubtedly emigration and natural disasters played a part in this depopulation, ongoing processes were also important. In particular, replacement levels were never sufficient to maintain a constant population size. In the early part of this period the main factor responsible was heavy neonatal mortality, almost all from tetanus (‘eight-day sickness’), but latterly the fertility of those who survived was low, even though mortality rates had declined. In part at least, this decline in fertility could be ascribed to a lower frequency of marriage—a phenomenon seen elsewhere in the Outer Hebrides during the latter part of the 19th century.

Estimates of the opportunity for selective pressure on the population suggest very high levels, due earlier mainly to high pre-reproductive mortality and later to lowered fertility.

An investigation of the incidence and pattern of non-marital pregnancies in New Zealand, and their outcome as nuptial or ex-nuptial births, has revealed four major features. The post-war period has been marked by a steady increase in the incidence of non-marital pregnancies, especially since the early 1960s (following the inclusion of Maori vital events). Pre-marital or bridal pregnancies increased during the 1950s, but have steadily declined at all ages between 16 and 23 years during the 1960s and early 1970s. Nuptial fertility rates for women aged 35 years and over have declined continuously since 1945, and since the early 1960s the decline has commenced for women at younger ages as well. Ex-nuptial fertility rates have been increasing throughout the post-war period and particularly since the early 1960s.

Frequently it is of interest to compare the distributions of birth intervals for two or more population subgroups. Such analysis can serve as a useful adjunct to conventional studies of differential fertility.

This paper discusses several statistical tests which can be used to test differences in the distributions of the length of birth order specific intervals when these distributions are obtained using life table techniques. Since such estimates involve incomplete or arbitrarily censored intervals, conventional statistical tests are not appropriate.

The tests are illustrated through application to data from the 1965 National Fertility Survey. Data on the occurrence and timing of third and fourth births are shown to be significantly different for black and white currently married women. Comparisons among income groups, however, fail to show significant differences.

In adult life the human breast, unlike that of other species, is sufficiently developed to allow milk secretion to occur after only a brief period of hormonal stimulation. During pregnancy the ducts and secretory alveoli develop under the influence of both oestrogen and progesterone. Growth hormone and placental lactogen are not required; the role of prolactin in mammogenesis remains questionable. Lactogenesis, the onset of milk secretion, is inhibited during pregnancy despite high levels of prolactin, by a direct inhibitory action of steroids on the breast. The clearance of placental steroids after delivery removes this inhibition and milk secretion is initiated.

Inhibition of prolactin secretion prevents milk secretion, suggesting that prolactin is the essential hormone for lactation in man. Prolactin release occurs in response to suckling and the amount released depends on the strength and duration of the suckling process. No release of prolactin occurs in response to stimuli other than stimulation of the nipple.

Removal of milk from the mammary gland is effected by the milk-ejection reflex (MER) involving the release of oxytocin in response to suckling. Unlike prolactin, oxytocin may be released in response to stimuli associated with breast-feeding, e.g. the cry of the infant. The MER may be inhibited by psychological and physical stress, either by inhibiting oxytocin release or by preventing its action upon the breast contractile elements. The susceptibility of the MER to disturbance requires consideration when encouraging the establishment of breast-feeding.

Breast-feeding is geared directly to the needs of the infant, since not only does the suckling infant obtain its present meal by inducing oxytocin release, but also by stimulating prolactin release it orders the next (Tindal, 1972).

Despite the great amount of resources invested in family planning programs around the world and the considerable attention given to appraising their effects, little has been written about the analysis of family planning costs. Indeed, costs often seem to be virtually ignored. In the likely event that the growth of resources available for financing family planning programs in the future ceases to be as high as the expansion in demand for family planning, pressures will develop for better ways of evaluating family planning costs. This paper considers two major methodological issues—what should be included in family planning costs and what is the most practically useful classification. First, we recommend the use of a complete, inclusive concept of economic costs, including the imputation of costs of ‘free’ or donated inputs. Second, a classification of costs into administrative, motivational and contraceptive is suggested. The location of the usual types of family planning in these categories is then indicated.

Both the concept of economic costs and their three-fold classification are illustrated with detailed data on the family program in Barbados from its inception in 1955 through 1974.

An ever-changing secretory pattern of pituitary gonadotrophins and prolactin has been observed in puerperally lactating women. Studies in our laboratory suggest such changes are under neurogenic control via the breast. This in turn alters hypothalamic function. Endocrine profiles in lactating women obtained over 10 hours indicate that prolactin secretion and, to a lesser extent, LH secretion, are directly related to the duration and intensity of the suckling stimulus. Thus, lactation performance governs pituitary-ovarian function. Other investigators have shown that alterations in hypothalamic catecholamine turnover represents the interface between nipple stimulation and subsequent pituitary hormone secretion. Although further work is necessary to elucidate the exact neuroendocrine pathways involved, full lactation will effectively delay the restoration of cyclic gonadotrophin secretion and ovulation.

A sample of 442 males living in Amsterdam and convicted for ill-treatment without malice prepense in 1970 and 1971, was drawn from the files of the Central Bureau of Statistics in The Netherlands to study a possible relationship between the birth month of male offenders, the annual period of perpetration and the age at which the offence is committed. The results suggest that in Amsterdam the perpetration of aggressive delinquencies during the annual period is to some degree correlated with the (calendar) month of birth. It seems that particular seasonal conditions only have an effect if these occur within a limited period before or after the birth month. Additionally, a long-term effect has been found, showing that the age at which the offence is committed is to some degree correlated with the month of birth. So far, causal factors are not known. However, other studies suggest the influence of seasonal meteorological conditions, although periodical social factors should not be excluded.

A study of the differentials in fertility of Iraq's Mohafadhas, and the association of fertility with various socio-cultural factors, is handicapped for want of the reliable vital statistics from which measures of fertility can be satisfactorily derived. The alternative method, using a simple measure of fertility, the child–woman ratio, which requires only a knowledge of the population in age groups is therefore used. Since this measure is computed from census statistics, it is affected by differences in enumeration errors and in mortality and migration. An attempt has been made in this paper to keep these factors constant by using a modified child–woman ratio for comparing fertility levels.

The analysis showed that fertility rates vary from region to region, between Mohafadhas within a region and between rural and urban areas. One important broad geographic variation was that the Northern region was the area of high fertility. For the Mohafadhas, significant differences were noted in only six of the sixteen Mohafadhas of Iraq. Rural–urban difference was minimal, with few exceptions, and it was not always in the same direction. The intra-rural variations in the fertility ratio were far more important than intra-urban differences.

Correlation analysis showed that the average age at marriage, the proportion never married and the sex ratio in the reproductive ages were the important factors in explaining fertility differences between Mohafad has. There was virtually no correlation between fertility and urbanization or literacy.

A preliminary breakdown of the characteristics of all new attenders at a Dublin family planning clinic during the first 6 months of 1974, showed that just under half of those attending were unmarried at the time of their first visit. Of these single women, three in five planned to marry shortly and two in five had no marriage plans. The main part of the study concentrates on this latter group. A sample of 50 women was interviewed and the results provide some factual data on their family and educational background, their sexual and contraceptive behaviour and their attitudes to related issues. They came mainly from upper-middle income groups and had a high standard of education. Although they were, almost without exception, born into Roman Catholic families, only just over a quarter were regular church attenders. All but 6% were already sexually experienced at the time of their first visit and most were now involved in a stable sexual relationship which involved having intercourse at least once a month; while well informed on contraception, only a small minority had always used a reliable method. Since the mean interval between first intercourse and their first visit to the clinic was over 2.2 years, the majority had been at risk of becoming pregnant. One in six of those interviewed had experienced pregnancy and half of these had sought an abortion. While 76% of the sample considered abortion acceptable in at least extreme cases, only 12% were without strong moral reservations; in the event of pregnancy 32% would consider seeking an abortion. A correlational analysis of some of the results is presented.