How Cognitive Genetic Factors Influence Fertility Outcomes: A Mediational SEM Analysis

Utilizing a newly released cognitive Polygenic Score (PGS) from Wave IV of Add Health (n = 1,886), structural equation models (SEMs) examining the relationship between PGS and fertility (which is approximately 50% complete in the present sample), employing measures of verbal IQ and educational attainment as potential mediators, were estimated. The results of indirect pathway models revealed that verbal IQ mediates the positive relationship between PGS and educational attainment, and educational attainment in turn mediates the negative relationship between verbal IQ and a latent fertility measure. The direct path from PGS to fertility was non-significant. The model was robust to controlling for age, sex, and race; furthermore, the results of a multigroup SEM revealed no significant differences in the estimated path coeficients across sex. These results indicate that those predisposed towards higher verbal IQ by virtue of higher PGS values are also predisposed towards trading fertility against time spent in education, which contributes to those with higher PGS values producing fewer offspring at this stage in their life course.

How cognitive genetic factors influence fertility outcomes: A mediational SEM analysis

ABSTRACTUtilizing a newly released cognitive Polygenic Score (PGS) from Wave IV of Add Health (n = 1,886), structural equation models (SEMs) examining the relationship between PGS and fertility (which is approximately 50% complete in the present sample), utilizing measures of verbal IQ and educational attainment as potential mediators, were estimated. The results of indirect pathway models revealed that verbal IQ mediates the positive relationship between PGS and educational attainment, and educational attainment in turn mediates the negative relationship between IQ and a latent fertility measure. The direct path from PGS to fertility was non-significant. The model was robust to controlling for age, sex and race, furthermore the results of a multi-group SEM revealed no significant differences in the estimated path coefficients across sex. These results indicate that those predisposed towards higher IQ by virtue of higher PGS values are also predisposed towards trading fertility against time spent in education, which contributes to those with higher PGS values producing fewer offspring.

Medición de la baja fecundidad: repensando los métodos demográficos / Measuring Low Fertility: Rethinking Demographic Methods

En el análisis de la fecundidad baja cobra importancia una serie de conceptos básicos como la progresión de paridad a partir de tablas de vida –aquí llamadas tablas de fecundidad–, y la consideración de los efectos de los cambios de calendario sobre las tasas de fecundidad observadas. En este artículo se presenta la génesis histórica de estos conceptos y su relación con otros similares –como la traslación demográfica–, acompañados de ejemplos de aplicación en el análisis de la fecundidad de periodo y de cohorte. Algunas investigaciones recientes, entre las que se incluyen las de los autores, permiten hoy en día obtener intensidades de fecundidad ajustadas por calendario, a partir de las cuales se pueden conseguir todo tipo de medidas de fecundidad de periodo libres de efectos calendario o proyectar la fecundidad a partir del método de progresión de paridad. AbstractIn a low fertility context there are a number of basic concepts that become more relevant for the analysis of fertility, such as parity progression analysis through life-table methods, here called fertility tables, and the consideration of the effects of tempo change on observed fertility rates. In this articles, these ideas are presented together with their historical genesis and their relationship to similar concepts such as demographic translation, together with examples of application to both period and cohort fertility analysis. Recent research, including research done by the authors, allow us today to estimate tempo-ad­justed fertility intensities that can be used to obtain any tempo-adjusted period fertility measure or parity-progression fertility projections.