Amniotic fluid prolactin levels and lecithin/sphingomyelin ratios during the third trimester of human gestation

Prolactin levels in amniotic fluid during the third trimester of human pregnancy showed a wide range of values. There was no apparent correlation between amniotic fluid prolactin concentrations (AF PRL) and lecithin/sphingomyelin (L/S) ratios nor was there a prolactin concentration associated with a mature L/S ratio. There was no correlation between AF PRL concentration and estimated gestational age or neonatal birth weight. In patients with diabetes mellitus (White Classes A to C), AF PRL were higher prior to 37 weeks, or when the L/S ratio was less than 2, than after 37 weeks, or when the L/S ratio was greater than 2.