A new estimate of permanent sterility by age: Sterility defined as the inability to conceive

Abstract

The proportion of couples permanently sterile beyond a certain age is an important component of the reproductive process. Unless medical assistance is used, this age is the upper bound of the fecund period. Most estimates of sterility by age of the woman have been derived from natural fertility populations, in which the number of births and the timing of the last birth (of the complete reproductive history) were not controlled by the couples. Because data on these populations do not include pregnancies not ending in a live birth, the sterility estimates apply to the proportion of couples unable to conceive and to have a live birth. For this reason, it is useful to have an estimate of sterility based on the risk of conceiving, independently of the fate of the pregnancy. Using this new estimate, sterility increases with age much more slowly than with most previous estimates.

Keywords:

• sterility
• foetal wastage
• natural fertility

Notes

1. Henri Leridon is at the Institut national d’études démographiques (INED), 133 Boulevard Davout, 75980 Paris cedex 20, France, and at the Institut national de la santé et de la recherche médicale (INSERM, u822). E-mail: [email protected]

2. The author thanks two anonymous referees for their helpful comments.