Two Ghanaian women with sickle-cell anaemia and α-thalassaemia were found to have an unusually benign obstetric history. In addition to two factors present which are known to moderate the clinical course of sickle-cell anaemia, good socioeconomic status and a relatively high Hb F level, it is suggested that α-thalassaemia may act among other things by lowering the haemoglobin concentration in the red cells and thereby lowering their tendency to sickle in vivo.