Mean ages at parities: an indirect estimation.

"The objective of this paper is to describe an indirect approach for estimating the age patterns of occurrence of birth by parity. The main concern here is not of estimating the frequency of occurrence of births (in a period of time) in relation to the population (birth rate) or in relation to the number of females (fertility). Rather, the focus here is on the ages of first, second, and subsequent births, and on their shifts over time. Essentially, the approach is an extension of Hajnal's method for using proportions single to estimate singulate mean age at marriage...." The approach is illustrated using data from the 1975 Pakistan Fertility Survey and the 1990-1991 Pakistan Demographic and Health Survey. A comment by Sultan S. Hashmi is included (pp. 560-1).