Effect of declines in mortality on the birth rate and related measures

Abstract

These analyses do not demonstrate how changes in mortality which lead to differences in widowhood affect birth rates nor do they show how a fall in mortality will affect the birth rate when other factors such as marriage and age-specific marital fertility rates are held constant. These aspects were not considered by Coale and Tye in their recent study of the effects of changes in age patterns of fertility on growth and birth rates. They were concerned with the effects of changes from a younger to an older pattern of age-specific fertility rates on the growth and birth rates at the same level of mortality and on the total fertility rate or gross reproduction rate (G.R.R.). Hence in this present study we propose to examine the effects of changes in mortality on the birth rate and related measures such as growth rate mean length of generation mean duration of potentially fertile married life etc. when (i) the pattern and magnitude of age-specific marital fertility rates are held constant so that at a different level of mortality the age-specific fertility rates for all women change and hence the G.R.R. changes and (ii) the marriage is held constant to a large extent at both levels of mortality. (excerpt)