Prevalence of hyaline membrane disease in black and white low-birth-weight infants.

Previous studies in South Africa and elsewhere have suggested that there are ethnic differences in the prevalence of hyaline membrane disease (HMD). This study compared the prevalence of HMD between black and white infants with birth weights of 1,000-1,749 g. A cohort of black and one of white low-birth-weight infants were enrolled at Baragwanath and Johannesburg Hospitals respectively. Black infants were found to have a higher rate of intra-uterine growth retardation. When compared according to either birth weight or gestational age categories, black infants had a significantly lower prevalence of HMD. For example, between 29 and 34 weeks' gestation 36.2% of black and 62.5% of white infants developed HMD (P < 0.001). The reasons for these differences are not clear, however, and require further study.