Effect of diabetes mellitus on amniotic fluid lecithin/ sphingomyelin ratio and respiratory distress syndrome

Ninety-eight insulin-dependent diabetic patients were cared for during 1 08 pregnancies following an ambulatory program aimed at close con1rol of blood sugar levels. The irteidence of respiratory distJ:ess syndrome (RDS) in these patients was not different from that in nondiabetic patients. Fetal pulmonary maturity seemed to progress at a normal rate as evidenced by an equal incidence of mature lecithin/sphingomyelin (LIS) ratios at various st~es of gestation in diabetic and nondabetic patients. There was no evidence that Class B and C diabetic patients have delayed fetal lung maturation or that Class E, F, and R patients have accetefated maturation. It is concluded that careful metaboUc control of the pregnant diabetic patient resuHs in a normal process of fetal pulmonary maturation without increased riSk of RDS. (AM. J. OBSTET. GYNECOL: 135:10, 1979.)