Reproductive compensation in families segregating for Cooley's anaemia in Ferrara.

The reproductive performance of 100 families segregating for Cooley's anaemia was studied and compared to the performance of 127 control families. The control families were those of the sibs of the parents in the segregating families. No differences was found in the variables which might affect fertility and fecundity in control and thalassaemic families, although a different shape of the distribution of the number of births per family was found; the distribution had a higher variance in thalassaemics than in controls. The interval between the birth of a normal and an affected child is significantly longer than the interval between the birth of an affected child and a subsequent one. It was thought that these findings are indicative of reproductive compensation in families segregating for Cooley's anaemia, and of the moderate effect of the genetic counselling given to them.