The study examines the effects of nursing practices on the duration of lactation in middle-class American women. Thirty-two nursing mothers were followed for 2 years post-partum, data being collected at eight home visits by interview and by nursing records kept by the mothers. Those women who nursed frequently (>8/day) during exclusive breastfeeding remained amenorrhoeic longer than infrequent nursers, introduced supplements later and did not resume menses as promptly thereafter. They continued an hour or more of night nursing during supplemented nursing. Duration of exclusive nursing and night nursing after supplementation were the major influences on duration of amenorrhoea. Mothers' age, weight-for-height, and nursing frequency before supplementation showed no significant effect but night nursing after supplementation was a major factor in post-supplementation duration of amenorrhoea. Those women who both supplemented later and maintained an hour of night nursing after supplementing remained amenorrhoeic for 6–10 months longer than those who supplemented early and/or reduced subsequent night nursing.

Data from a sample interview survey conducted in Accra in 1982 show that there is a very high level of knowledge of contraceptive methods among mothers aged 25–39 years (92%). However, only about 41% of the women had ever used any form of contraception, and only 18% were using modern methods at the time of the study. This is low for a city where an official family planning programme has been in operation for 15 years, even when the confounding effects of availability and accessibility of services have been controlled for. Suggestions are made for increasing the effectiveness of such programmes.

The 1981 Bangladesh Contraceptive Prevalence Survey found that 55% of ever-married women had some knowledge of traditional methods of contraception and the overall level of ever use was 23%. There was a positive relationship between use and socioeconomic variables. Current use of traditional methods at 7·7% was only slightly below the figure for modern methods (10·9%). It is suggested that traditional methods still have an important role in family planning and that this should not be disregarded.

This study examines the factors affecting age at first marriage—place of residence, education, premarital work status, religion, husband's childhood residence, education and occupation. Women's education appears to be the strongest determinant of variation in marriage age, and all the other factors show statistically significant influences.

This paper examines the broad movements of Canadian period and cohort fertility over the last hundred years or so, and compares them with corresponding trends in the United States and other industrialized countries. The main movement in Canada was a decline in fertility extending from the nineteenth century to the present time, interrupted in the 1940s and 1950s by a ‘baby boom’. The long decline in cohort fertility is largely explained by the decrease in the proportions of families of six or more children. This decrease continued during the baby boom, but in these years was more than offset, though not for Catholics, by the effects of increases in the proportions of families with three, four, and five children.

A rapid decline in fertility took place in Suriname between 1962 and 1974, and then stopped. While this sudden stabilization is surprising, it is not unusual. Similar trends have occurred in some Caribbean and Latin-American countries. The 1962–74 fall in fertility in Suriname seems to have been due to a combination of socioeconomic factors and the activities of the Suriname Family Planning Association, founded in 1968.

Data were analysed from the 1973 surveys of the Nigerian segment of the Changing African Family (CAFN) Project which covered Yoruba women and men in Ibadan and the western state of Nigeria. The Yoruba women in monogamous unions and those in polygynous unions show slightly varying levels of fertility, measured as mean number of children ever born. Most of this variation can be attributed to other variables; type of union of the women does not significantly affect their fertility level.

This study examines the influence of Islam and Christianity (Catholicism and Protestantism) on fertility in rural Sierra Leone. Analyses using number of children ever born and number of living children for currently married women of childbearing ages 15–49 as measures of fertility show that Muslim fertility is lower than either Catholic or Protestant fertility net of relevant demographic and socioeconomic variables.

The interaction between wife's educational level and her religious affiliation was statistically significant for number of children ever born but not for number of living children. Religion is shown to be an important factor in differentiating fertility behaviour at different educational levels. Among wives with no schooling, differences in religion lead to small fertility differentials; among those with primary or higher education, the fertility differentials are substantial.

Census data were used to investigate the influences of socioeconomic and environmental variables on child mortality rates in southern Brazil. By multivariate logistic regression analysis the effects of correlated factors were distinguished, after adjustment for maternal age and parity. Low family income and, to a lesser degree, low employment status of the head of the family were associated with high child mortality levels. Place of residence, education of the mother and of the head of the family, availability of piped water in the home, access to a toilet and type of housing were all associated with childhood mortality variation, even after allowing for the effects of income and employment. The contributions of the source of the water supply and type of sanitation facilities, however, were less clear and tended to become unimportant after controlling for the socioeconomic variables. There was also no apparent advantage in being covered by government health insurance.

The effects of socioeconomic and geographical factors on age-specific mortality by suicide in men were assessed in 46 Japanese prefectures (counties) by stepwise regression analysis twice at 5-year intervals, before and after a serious economic crisis. The following factors were significantly related to the mortality in the two years: (1) the proportion of old and young men in the population for young men; (2) low income for middle-aged men; and (3) rural residence for elderly men. The mortality significantly increased after the crisis in young and middle-aged men, while no significant alteration was observed in elderly men. It is suggested that young and middle-aged men are more sensitive to socioeconomic changes in society while elderly men are mainly affected by the factor of rural residence.

Application of a multivariate analytical technique to the World Fertility Survey data for Java and Bali indicates that demographic variables, particularly the length of the preceding birth interval, are more important in explaining infant and child mortality differentials than are such social variables as education of parents or urban–rural residence. These findings are weakened to some extent by the lack of satisfactory data on household economic status which might have provided a better base for indirectly discerning the effects of nutrition and sanitation on mortality at young ages.