The Sherpas of Upper Khumbu (above 10,000 feet), Nepal, and their migrant counterparts at lower altitudes (3000–7000 feet) in Darjeeling District, West Bengal, show no statistically significant difference in age–sex structure or mortality, while there are suggestions of some fertility reduction at the higher altitudes.

Mirpur is a small village of 320 individuals in coastal Midnapore district, West Bengal, the inhabitants of which claim partial Portuguese ancestry. The demographic data collected in Mirpur are reported here. The age structure of the population suggests a growing population trend, but a constriction at the base of the pyramid indicates a recent decline of fertility. The completed family size, net reproductive index and total fertility rate are also compatible with high growth rate, but the age-specific fertility rates are lower in the younger than in the older women. The infant mortality rate is low in general, and is lower in the offspring of the younger women. The Mirpurians suffer from protein-calorie malnutrition and heavy intestinal parasitic load. The possible relationships among high fertility, malnutrition and high parasitic load are discussed.

Urine was collected at weekly intervals for 3 months from 254 menstruant women aged 15–39 years, all of whom were 4 or more years from the menarche. Menstrual cycles were classed as ovulatory if the 24-hr pregnanediol output was 5 μmol or over on a single occasion, or if the total excreted on 2 days, 1 week apart, was 7 μmol or over. Of the 108 women aged 20–24 years, only 62% ovulated in every cycle compared with 88% for the 58 women aged 25–29 years, and 91% for the 44 women aged 30 or over. Unfailing ovulation occurred more often in non-students (99 women, of whom 83·5% ovulated in every cycle) than in age-matched students (111, 59·5%), and more often in women who lived with relatives (127, 83·5%) than in those living in flats and hostels (72, 51·4%).

Risk factors associated with childhood obesity were examined in children of the elementary school of Aosta (northern Italy). In data from 2044 families none of the variables investigated (sibship size, mother's age, birth rank, the ‘temporarily-one-child syndrome’, and number of living parents) was found to have a significant association with the frequency of obesity, though weak associations for family size and the number of living parents may exist. The only significant difference found was between children of parents from northern Italy and those from southern Italy (recent immigrants).

The rise in Caesarian section rates has been much greater in the United States than in Britain. This article analyses the reasons for these trends and finds they are not clearly related to good medical practice. It is concluded that it should be a cause for concern if rates rise above 6% of live births. In this case operations must be shown to be in the best interests of the mothers and their babies.