Lecithin Content of amniotic fluid in twin pregnancies with and without long-term tocolytic therapy

During the period from January 1973 to October 1979, 55 transabdominal amniocenteses were performed on 40 twin pregnancies and the lecithin content of the amniotic fluid obtained was established in order to determine the fetal lung maturity. The lecithin determination was performed densitometrically according to Kynast and Saling. Through long-term tocolysis in twins the surfactant production rate is delayed in each phase of the pregnancy, whereas in a collective without long-term tocolysis one can reckon with sufficient fetal lung maturity from the 35th week onwards.