[Heritability of fertility in human populations and the structure of Crow's index]

Heritability of fertility was determined in populations with natural character of reproduction (Middle Asia Republics) and in populations with family planning (Middle Russia). The material was collected by interviewing the married women of postreproductive age. The heritability of fertility was estimated as a doubled coefficient of correlations between sisters for effective fertility. In populations with natural character of reproduction the heritability was about 50% and it did not differ from O in the populations with family planning. The values of heritability were used in the components of the Crow index analysis. The main contribution into broad-sense heritability of fertility comes from additive component, as shown in an Asia population (Turkmen). The values of heritability of fecundability (86%) and of postpartum sterility (66%) have been calculated for the same population.