Use of the TDx-FLM assay in evaluating fetal lung maturity in an insulin-dependent diabetic population. The Diabetes and Fetal Maturity Study Group.

OBJECTIVE: To assess the usefulness of the recently introduced TDx-FLM assay in managing pregnant women with diabetes.

METHODS: Participating institutions were recruited from the 1993 and 1994 Society of Perinatal Obstetricians Diabetes Special Interest Group meetings. Study patients consisted of insulin-dependent diabetic women who had undergone transabdominal amniocentesis with assay of the fluid by the TDx-FLM method. Pertinent data were requested concerning pregnancy and respiratory outcomes of the corresponding neonates.

RESULTS: Data from 261 pregnancies at 13 institutions were collected. Eight of the 182 infants born within 4 days of amniocentesis developed respiratory distress syndrome (RDS); five of the eight infants with RDS required intubation, and all five had TDx-FLM values less than 70 mg of surfactant per gram of albumin. Three of the eight infants with RDS required hood oxygen only; two of these infants had TDx-FLM values at least 70 mg/g. Thirteen of 144 (9%) subjects who delivered within 4 days of amniocentesis and for whom a TDx-FLM assay and phosphatidylglycerol level were both reported had a TDx-FLM level of at least 70 mg/g and a negative phosphatidylglycerol result. No infant with this combination of results developed RDS. Fifteen of the 40 patients who delivered more than 4 days after amniocentesis, with both tests available, had TDx-FLM values at least 70 mg/g and were phosphatidylglycerol negative.

CONCLUSION: In infants of diabetic mothers, TDx-FLM values at least 70 mg/g were not associated with RDS requiring intubation. The TDx-FLM assay may be useful in determining the best time of delivery for pregnant patients with diabetes, especially in a situation in which the TDx-FLM assay is mature and the phosphatidylglycerol result is immature.