Title: An aggregate fertility model.

POPLINE Document Number: 266700

Author(s):

Bongaarts J
Potter RG

Source citation:

In: Bongaarts J, Potter RG. Fertility, biology, and behavior: an analysis of the proximate determinants. New York, New York, Academic Press, 1983. :78-102. (Studies in population)

Abstract:

A simple but comprehensive model for the relationship between the proximate determinants and a set of aggregate fertility measures, including the total fertility rate (TFR) and total marital fertility rate (TM) are presented. 4 of the proximate variables--marriage, contraception, induced abortion, and postpartum infecundability--are considered the principal determinants of fertility, whereas the remaining 3 proximate variables--natural fecundability, spontaneous intrauterine mortality, and permanent sterility--are treated as generally much less important determinants. A test of the model with data from 41 developing, developed, and historical populations indicates that the 4 principal proximate determinants explain 96% of the variance in the observed TFRs of these populations, thus confirming the general validity of the model and the hypotheses about the operation of the reproductive process incorporated in it. The effects of variations in the proximate variables on levels of overall, marital, and natural fertility were examined with the model. This analysis demonstrates that each of the principal proximate variables can have a large impact on fertility and that any given level of fertility can be obtained by a variety of combinations of the proximate determinants. As a consequence, populations with the same TFR do not necessarily, and in fact only rarely, have the same set of proximate determinants. It is also noted that marital fertility may temporarily rise during an early phase of the demographic transition if the fertility enhancing effect of a decline in breastfeeding or postpartum abstinence is not offset by a sufficiently rapid increase in the practice of contraception or induced abortion.

Keywords:

Fertility Determinants
Fertility Rate
Total Fertility Rate
Models, Theoretical
Mathematical Model
Research Report
Summary Report
Marriage
Contraception
Abortion
Abortion, Spontaneous
Natural Fertility
Fecundability
Historical Demography
Developing Countries
Developed Countries
Breastfeeding
Abstinence
Postpartum Amenorrhea
Correlation Studies
Fertility
Population Dynamics
Demographic Factors
Population
Birth Rate
Fertility Measurements
Research Methodology
Nuptiality
Family Planning
Fertility Control, Postconception
Pregnancy Complications
Diseases
Fecundity
Reproduction
Demography
Social Sciences
Infant Nutrition
Nutrition
Health
Family Planning, Behavioral Methods
Puerperium
Statistical Studies
Studies