Volume 6 - Article 14 | Pages 383-408

The Fertility Pattern of Twins and the General Population Compared: Evidence from Danish Cohorts 1945-64

By Hans-Peter Kohler, Lisbeth B. Knudsen, Axel Skytthe, Kaare Christensen


Date received:	11 Feb 2002
Date published:	24 May 2002
Word count:	5512
Keywords:	cohort fertility, Denmark, fertility, twin studies
DOI:	10.4054/DemRes.2002.6.14

Abstract

Twin studies provide an important possibility for demographers to analyze patterns of heritability and to estimate structural models with controls for endowments. These possibilities are increasingly used in the context of fertility and related behaviors. A close congruence between the fertility patterns of twins and that of the general population, however, is an essential pre-condition in order to generalize the results of twin-based investigations of fertility and related behaviors to the general population.
In this paper we therefore compare the fertility of Danish twins born 1945--64 to the fertility pattern of the general population born during the same period. Our analyses find a very close correspondence between the fertility pattern of twins and of the general population. There exist only few statistically significant differences, and the primary difference pertains to the fact that female twins have a slightly later onset of childbearing than non-twins. There are virtually no relevant differences between the fertility patterns of dizygotic and monozygotic twins.

Author's Affiliation

Hans-Peter Kohler - University of Pennsylvania, United States of America [Email]
Lisbeth B. Knudsen - Aalborg University, Denmark [Email]
Axel Skytthe - University of Southern Denmark, Odense, Denmark [Email]
Kaare Christensen - University of Southern Denmark, Odense, Denmark [Email]