A safe method of amniocentesis for lecithin/sphingomyelin determination in late pregnancy using ultrasound.

Two hundred consecutive amniocenteses for lecithin/sphingomyelin (L/S) determination in late pregnancy are reviewed. These procedures were performed under ultrasonic control before induction of labor or elective cesarean section in a prospective study to determine a safe method for aminocentesis. Complications included 3 failures, 14 blood-stained samples, 2 cases of labor occuring within 24 hours after amniocentesis, and 1 maternal abdominal wall hematoma. There was no cases of perinatal morbidity or mortality. It is proposed that this is a safe method of abdominal amniocentesis for L/S determination in late pregnancy.