Book reviews

Data from Hungary and Sweden are used to investigate the extent to which prematurity confounds the relationship between length of preceding birth interval and perinatal mortality. Controlling for length of gestation removes between 65 and 90 per cent of the excess mortality associated with birth intervals of less than 18 months; however, mortality among infants who are born less than 18 months after the birth of their previous sibling is still higher than among infants born after longer intervals. These results suggest that, although short birth intervals are associated with high perinatal mortality, estimates of the risks attributable to birth-spacing are overstated, if length of gestation is not taken into account.