Is human mating for height associated with fertility? Results from a British National Cohort Study.

Abstract

Very few studies have investigated whether spousal similarity for height is related to fertility. This study examined the relationship between mating for height and fertility after correction for spousal age, social class, education, and region. The data used were collected as part of the British National Child Development Study and 6,535 husband-wife pairs for whom data were available on measured height, spousal age, education, social class, region, and the number of children were studied. Fertility varied between the regions with the highest fertility in Scotland. Fertility tended to increase from more to less educated and from higher to lower social classes in both sexes. These relationships remained significant after correction for mean age. A negative association between husband's height in relation to fertility was noted as well as the negative and the quadratic term for wife's height. Both the linear as well as the quadratic effects of parental height difference were significantly related to fertility, but after removing the effects of mean age, age difference and mean height these effects disappeared. Analysis of region, mean age, social class, education, height, and differences in age, social class, education, and height together revealed that 32.4% of variation in fertility was explained but only mean age, mean social class and mean height and difference in social class remained significant. The results did not provide any evidence that differential fertility was associated with spousal height difference after taking into account age, social class, education and region.