AGE OF MOTHER AT LAST BIRTH IN 2 HISTORICAL POPULATIONS

This study uses sets of historical family reconstitutions from all of Quebec and from four villages of the Haut-Jura, France-first marriages of 2226 and 994 women, respectively-to investigate the physiological and social factors affecting age of mother at last birth before and du ring fertility transition. Age remained high throughout the period cov ered in Quebec, under 'natural' conditions, but showed a steady declin e in the French material which extends to late 19th century generation s practising family limitation. Age at marriage had no influence in Qu ebec; in France, however, women with the most surviving children at ag e 35 continued childbearing the latest. There was no link between biol ogical ability to achieve a live birth, or in health status or aging r hythm, and age at last birth. Behaviour of mothers and daughters showe d no relation. The variability in age at last birth thus appears to be random under natural conditions; with the onset of controls, social d ifferences seem to influence not only the end of childbearing, but all aspects of behaviour governing final family size and child survival.